With the NAB Challenge approaching, AFL.com.au will examine all the defenders, midfielders and forwards on your club's list.  

Today, we assess the backmen from Adelaide through to Greater Western Sydney. Tomorrow, we look at Hawthorn to the Western Bulldogs.

ADELAIDE
Luke Brown: Impressive 2013 season and is striving to increase his offensive output as well as his on-field leadership. Along with Rory Laird, Brown has established himself as a best-22 player.
Cam Ellis-Yolmen: Hasn't consistently produced his best, but coaches insist he's got X-factor that could see him become something special. Big year of development in the SANFL ahead and possible AFL debut.
Kyle Hartigan: Showed he has what is needed in the AFL last year and will replace Ben Rutten at times in 2014. His first full pre-season has done his fitness a world of good.
Ricky Henderson: Hugely important versatile player who looked at home in defence last year before injury ended his season. He's recovered from knee surgery and appears likely to play prior to round one.
Jake Kelly: The coaching staff say they've had to reel Kelly in this summer, such is his thirst for the contest. He'll start the season as a rookie, but summer form suggests an elevation is a possibility.
Rory Laird: Really cemented his place in defence last year and coaches love his attitude. He's a hard worker on the track and does plenty of homework on the opposition.
Andy Otten: Knee issues restrained him prior to Christmas but Otten is fast returning to full training in his quest to back up a sensational 2013 season that saw him become a versatile defender/forward.
Brent Reilly: Shoulder surgery has hindered his pre-season but he's almost back to full training. He's managed most of the club's running, so his fitness levels are solid. Might play a trial before round one.
Ben Rutten: The 30-year-old hasn't shown any sign of slowing down this summer. Set to reduce his workload this year to ensure he's fresh at the business end of the season.
Sam Shaw: His body really let him down in 2013 but he's unscathed so far this summer and is like a new recruit this year. Flexible key-position player who coaches say could find himself in attack as well as defence this season.
Sam Siggins: Still pretty raw, but with plenty of promise. He's unlikely to see AFL action this season but will benefit from playing with Adelaide's SANFL side this year.
Daniel Talia: Continues to go from strength to strength and has hardly missed a session this pre-season. Will be looking to increase his on-field leadership in 2014 as he becomes one of the club's elites.
Luke Thompson: Has enjoyed a great, injury-free pre-season and coaches have been impressed with how he's looked on the track. Failed to play a senior game last year due to injury. - Harry Thring

BRISBANE LIONS
Jed Adcock: The backline general is now also the sole skipper after taking the reigns from Jonathan Brown. Can lock down smaller opponents and leads by example with his fearless attack on the ball.
Jordon Bourke: A rookie with one season under his belt and despite some good signs late in the 2013 NEAFL season, still likely to need another year or two of development before nudging senior selection.
Justin Clarke: Huge improver last year in his 14 games, and a big chance to start alongside Daniel Merrett in a key defensive post. Has overcome shoulder surgery and is back into full contact work.
Tom Cutler: Draftee taken as a third defender that can play on both talls and smalls. Likely to start the season in the twos.
Darcy Gardiner: Drafted as a key defender, but at 191cm and with good pace, is likely to switch between defensive posts. Has been in the rehab group with a shoulder injury and will ease his way into the season.
Mitch Golby: Quickly becoming one of the most crucial players in the back half, the 22-year-old has excellent foot skills and is reliable in a one-on-one situation. Golby plays back pocket, and is an emerging leader who is ready to take another step up.
Ryan Harwood: In and out of the team over his first four seasons, Harwood played 12 of the final 13 games in 2013 and now has the chance to cement a spot at half-back. Has excellent speed, loves to take a bounce and should get first crack.
Matt Maguire: Now 29, the former Saint has been excellent when on the park the past two years. Might start behind Clarke in the battle for a starting spot, but is great insurance and won't let anyone down when he gets a chance.
Daniel McStay: Another draftee that will need time in the reserves, McStay is a tall defender that should learn plenty behind Merrett and Maguire.
Daniel Merrett: Has been used forward out of necessity in recent years, but no doubt the Lions are best when Merrett is at full-back. Fully recovered from a broken ankle and will start in round 1.
Joel Patfull: The back-to-back best and fairest is one of the most under-rated players in the League. Patfull is ideally used as a third defender, but can play on talls and smalls and is one of the first players picked each week.
Patrick Wearden: Has been in the system two years and looks ready to push for a senior debut across half-back. Consistent reserves performer who is courageous and a good decision-maker. - Michael Whiting




The Lions have swung full-back Daniel Merrett forward in recent years. Picture: AFL Media

CARLTON
Josh Bootsma: The tall, lean runner needs to make inroads but will presumably find it difficult to establish himself in the Blues' backline given several others appear ahead of him. Entering his third season, he signed a new two-year deal last August before being discussed at the trade table.
Sam Docherty: In his first pre-season with the Blues, the former Brisbane Lion has impressed with his approach and appears likely to be given an early opportunity to impress in defence.
Andrejs Everitt: The ex-Swan and Bulldog arrived at Carlton in the best shape of his career after completing a rigorous martial arts camp in Thailand during the off-season. The Blues are excited by the flexibility he provides as a half-back/wingman.
Cameron Giles: The No. 39 draft pick – a tall, dashing backman who could develop into a swingman and back-up ruckman – was eased into the pre-season workload but could come into contention for a third-tall defensive role at some stage this season.
Michael Jamison: Shoulders permitting, the longtime backline leader will be primed to enhance his standing among the AFL's best full-backs. Also has an important role in helping to school defensive hope Matthew Watson.
Andrew McInnes: The disciplined defender is probably vying with Simon White and perhaps even Everitt for the third-tall defensive role. His ability to also play on a small forward could prove the difference at times.
Heath Scotland: Carlton's oldest player is now on the club's rookie list but, far from being simply a back-up option, the 33-year-old is still favoured to be a regular member of the Blues' back six. A steadying influence.
Kade Simpson: The Blues' reigning club champion thrived after being shifted to half-back, and coach Mick Malthouse likes backmen who are courageous, composed and use the ball well, so Simpson appears destined for a similar role.
Zach Tuohy: The vigorous Irishman played mainly as a lockdown defender last year and could expand his game to have the occasional run on a wing, where his long kicking could provide another scoring option.
Andrew Walker: The versatile, high-leaping dasher is expected to continue as a back-half playmaker but the arrival of the likes of Docherty and Everitt could give the Blues the luxury of throwing Walker forward occasionally, adding some much-needed unpredictability.
Matthew Watson: The big left-footer has set his sights on holding down a key defensive position, both for his own development and to enable Lachie Henderson to play predominantly in attack. Has recovered well from a late-season broken foot.
Simon White: After suffering a season-ending fractured neck last year, the utility has made a full recovery and is on track to add significantly to his career tally of 26 games. - Ben Collins

COLLINGWOOD
Tony Armstrong: Transferred from the Sydney Swans in the off-season and has settled in well at the Westpac Centre. Armstrong's ball use will be an asset for the Pies, but he faces a tough task breaking into the best 22.
Nathan Brown: With the structure of the Pies' backline still a work in progress, this year shapes as a decisive season for Brown. Locking down on his opponent comes naturally, but the Pies will be hoping he can develop some attacking flair to complement his defensive skills.
Jack Frost: The rookie bolted to play the first four games last season, before a knee injury cut short a promising start to his career. May face limited opportunities if Reid, Brown and Maxwell are all fit.
Corey Gault: The versatile youngster played at both ends of the ground in the VFL last season. As a defender, he held his own against Joe Daniher and Jesse Hogan, before a groin injury ended his season. Set for another development year.
Lachlan Keeffe: Bounced back from a serious knee injury to play the final eight games of the 2013 season. He has outstanding athleticism and his football knowledge is getting better with each match he plays. Added to the leadership group during the week.
Nick Maxwell: Has relinquished the captaincy and will now turn his sole attention to leading Collingwood's backline. The 30-year-old is the chief organiser of the defence and plays a crucial role in chopping off the opposition's scoring opportunities.
Adam Oxley: Added to the senior list after a dominant year in the VFL. Oxley is very much in the Heath Shaw-mould as a rebounding defender and could push for senior selection early in the season. One to watch.
Ben Reid: Will Reid play in defence or up forward? The 24-year-old is an All Australian calibre defender, but he had great success when playing close to goal last year. Will be called upon to do a bit of both in 2014, but his starting position is likely to be in defence.
Paul Seedsman: Hip surgery will force Seedsman to miss the start of the season, so the dashing defender will likely have to work his way up from the VFL. Showed significant improvement in 2013 and is on the upward trend.
Ben Sinclair: Had shoulder surgery at the end of the season and is nearly in full training. Transformed himself into a lockdown small defender after Toovey was lost for the year. The competition for that small defender role is on in earnest.
Alan Toovey: Has worked methodically in his rehab from a torn ACL suffered on Anzac Day last year. Toovey's dependability was missed dearly in 2013 and his return will strengthen the Magpies' backline. On track for round one.
Marley Williams: A top-10 finish (seventh) in the club's 2013 best and fairest count capped a terrific season for the 20-year-old. Williams' preparedness to attack the ball, in the air or on the ground, won him plenty of admirers in 2013.
Peter Yagmoor: Yagmoor responded to his demotion to the rookie list with a solid year at VFL level. His precision kicking was a clear stand out. Likely to spend another year in the VFL, further learning the nuances of the game. - Ben Guthrie


ESSENDON
Jason Ashby: Although he wasn't able to break through for a senior game last year, the club is happy with Ashby's progress. Into his second season, the 19-year-old is a smart mover expected to get an AFL opportunity this season. 
Kurt Aylett: Recruited to the Bombers from the Giants last year, Aylett has pace and running ability. He can play across a few positions, but likes to take the game on. When fully fit he uses his athleticism well.
Mark Baguley: The former rookie's development last year was underlined when he was named the club's most improved player. A lock-down defender, Baguley held the likes of goalsneaks Eddie Betts and Stephen Milne to quiet games last year.
Alex Browne: A big year for Browne, who is into his fourth season with the Bombers. Attacks the ball, runs with it and makes things happen, and can also shift up to the midfield. Running and intensity has improved and will be looking to build on his eight career games.
Lauchlan Dalgleish: The quick half-back broke into the team for the final three games of 2013. If he can establish himself in the Bombers' defence it may release Hibberd or Dempsey to play a more offensive role. 
Courtenay Dempsey: A chest injury put Dempsey out for a few weeks last year before a severe hamstring tear ended his season in round 19. His run and carry off half-back makes him one of the club's most important players when fit. 
Shaun Edwards: Edwards can play all over the ground, an attribute which attracted the Bombers to the former Giant. Has an AFL grounding and good height to match his pace. Pre-season has been solid when on the track.
Dustin Fletcher: Set to be used spasmodically according to Thompson, Fletcher needs just one more match to become Essendon's leading games player. Has trained well over summer.
Sean Gregory: Was identified as soon as he was drafted in 2012 as a project player, given his lean frame – only 76kg – but he finds a way to spoil when he looks out of a contest and is improving. 
Cale Hooker: An important cog in a functioning Essendon line-up. The club's leading intercept marker and often takes the opposition's best forward, too.
Michael Hibberd: A quality performer in 2013, having a breakout season for the club across half-back with his strong marking and piercing left-foot kick. May spend some time even further up the ground this year.
Michael Hurley: Hurley has trained all pre-season as a defender and new coach Mark Thompson says he will play him in the backline and leave him there. Aggressive and strong, Hurley will be looking for his most consistent season after injury niggles in 2013. In full training after post-season surgeries.
Tayte Pears: Enters perhaps the most important season of his career. Has struggled to play consistently in the seniors since his navicular injury several seasons ago, but signed a two-year deal last year and is determined to make a backline spot his.
Dylan van Unen: Didn't make a huge impact in the VFL last year, despite being recruited as a mature-ager via Frankston. Reads the ball well and can set up the play. - Callum Twomey


Essendon's Michael Hurley is set to find his home in defence this year. Picture: AFL Media

FREMANTLE
Zac Dawson: Played 24 matches last season and has trained without interruption during the pre-season. One of Ross Lyon's most trusted defenders and will be hoping for another consistent year.
Paul Duffield: Only missed three games last year, with calf issues. Has had a strong pre-season and will continue to command the majority of the kick out duties. Could reach 150 games this season.
Garrick Ibbotson: Has just started to join main training after recovering from surgery to fix a tendinopathy issue in his Achilles. Was outstanding last season until the injury ended his year in round 19. Will push hard to get back into the first-choice 22 for round one.
Michael Johnson: Wonderful season in 2013, culminating in a richly deserved All Australian berth. Has been managed through the pre-season, but has been training with the main group fairly regularly and will be a key figure again.
Luke McPharlin: Missed eight weeks with a torn calf late in 2013 but played all three finals. Looks fit after a good pre-season. Should play the majority of the year but will be carefully monitored to avoid major injury.
Clancee Pearce: Had an excellent 2013 until he injured his Achilles in round 23 and missed the finals. Has been doing a lot of running away from the main group to regain full fitness. Looks strong and might be a chance for the NAB Challenge but more likely will push for round one. 
Alex Silvagni: Has been on a managed program in the pre-season. Played 10 matches in 2013 and signed a one-year extension. Will have to work hard to gain a permanent spot in the line-up.
Tanner Smith: Played just one match in his debut season against Hawthorn in round four. Is capable of playing both forward and back but Ross Lyon is keen for him to be a long-term defender. Has been matching up on Scott Gumbleton in match simulation drills. Could play the NAB Challenge but will need injuries to play in the premiership season.
Lee Spurr: Following his best season at AFL level, Spurr has been elevated to Freo's leadership group. Has been on an individual program through parts of the pre-season but should be fine for round one.
Cameron Sutcliffe: Turned from a specialist sub into a first-choice player last season. Played 19 matches including all three finals and won praise from his coach. Looks super fit and could push more through the midfield this season.
Tom Vandeleur: Pick No. 32 in the rookie draft. He's a versatile defender at 194cm and has participated in some of the main group work. Will be a project player and will spend time developing in the WAFL at Peel Thunder. - Alex Malcolm

GEELONG
Jimmy Bartel: There has been some talk down at the Cattery that Bartel will play more up forward this season, but last year the backline was his home. Great at launching chains of possessions that lead to scores.
Jed Bews: Was on the verge of breaking into the Cats' line-up last year and has been a strong performer during the pre-season. Earmarked to become an attacking defender.
Mitch Brown: Has been tried forward and back, but seems to have been more effective in the backline in recent years. Must take the next step this year.
Corey Enright: Brilliant reader of the play who was sorely missed in last year's preliminary final when he was sidelined by a knee injury. Is now full fit and ready to attack his 15th AFL season.
Cameron Guthrie: Being groomed to take over Enright's role. Played on Hayden Ballantyne, Angus Monfries and Cyril Rioli in last year's finals series and kept all of them goalless. Rarely beaten in a contest.
Joel Hamling: Project player who remains a project. Can also play up forward.
Taylor Hunt: Played as a shutdown midfielder last season but is set to spend a lot of time in the backline this year. Needs to rebuild his confidence.
Jake Kolodjashnij: Draftee who played as a key defender for Tasmania at last year's NAB AFL Under-18 Championships. Is elite when it comes to incept marks and intercept possessions. Could play an AFL game or two this year.
Tom Lonergan: Conceded the most goals of any player at Geelong last year but that was mainly because he lined up on the opposition's best forward most weeks. Will get the big jobs again this year.
Andrew Mackie: Made last year's All Australian team, which was great reward for many seasons of consistent play. Has the ability to stop an opponent but attack at the same time. Will again be a key player.
Jared Rivers: Had an indifferent first season at the club in 2013, with a knee injury sidelining him for a long period. Has had a big pre-season and should provide vital back-up for fellow key defenders Lonergan and Taylor.
Harry Taylor: Last year's All Australian centre half-back is perhaps the best key defender in the competition. Was involved in 60 one-on-one contests in 2013 and was only outmarked in one of them.
Jackson Thurlow: The Cats believe he is a star of the future. Had a slow start to the pre-season after needing hip surgery but has stepped up his workload since the Christmas break.
James Toohey (rookie): A project player who will be given plenty of time to develop in the VFL. - Adam McNicol




Geelong star Harry Taylor is one of the premier key defenders in the League. Picture: AFL Media

GOLD COAST
Jackson Allen: Two years in the system but will likely struggle to get games early. One of the best kicks in the club, but still tidying up other areas of his game.
Greg Broughton: Up and down first season at the Suns, but the 27-year-old former Docker brings experience and composure to a young backline.
Clay Cameron: An AIS Academy graduate, Cameron is being groomed as a long-term key position defender. Still a little way off, but wouldn't surprise if he played games as the year wore on.
Jack Hutchins: Was tried on the wing last year but drifted out of the team as the season wore on. Has speed and a defender's mentality, but will need to start the year well to win a spot.
Steven May: Played predominantly forward in 2013, but with Tom Lynch back fully fit, May will probably slide back to be a key defender with his size, speed and thumping left foot.
Trent McKenzie: One of the longest kicks in the AFL, McKenzie showed he was also an excellent one-on-one defender last season. Continues to improve and a crucial member of the side.
Tom Murphy: Traded in from Hawthorn before last season and proved just as vital with his voice as his actions. Terrific leadership qualities but will battle for a spot if everyone is fully fit.
Leigh Osborne: Rookie about to begin his second season, and despite playing one game late in 2013, will need some luck to crack it this year. Is a solid defender with a good left boot, but is a bit down the queue.
Henry Schade: Taken in the 2011 draft, the 20-year-old key defender is slowly adding size to his slim frame. Might need another year before seeing senior footy but is edging closer.
Matt Shaw: Big improver and highly under-rated. Shaw is aggressive and loves to take the game on. Should add plenty to his 52 games.
Seb Tape: Made a slow comeback last year after a knee reconstruction in 2012, but with a full pre-season behind him, should be in the round 1 team. Courageous and diligent, Tape is highly regarded and respected at the Suns.
Jeremy Taylor: Injury has restricted him to 10 games in three years, but Taylor is a terrific athlete and now has a full pre-season behind him. Down the pecking order and needs a huge year to retain his spot on the list.
Rory Thompson: After a breakthrough season in 2013, the red-haired fullback is already one of the Suns' most important players. Has overcome an off-season hip arthroscopy and will be available for Round 1.
Matthew Warnock: Been terrific since his acquisition from Melbourne two years ago, but a broken arm rubbed him out for most of last year. Might find it hard to squeeze in with the Suns looking to promote their young defenders. - Michael Whiting

GREATER WESTERN SYDNEY
Matt Buntine: A punctured lung heading into the 2013 season put him behind the eight ball, managing just three appearances for the year, and it's an important season ahead for the talented youngster.
Aidan Corr: The Irish-born defender showed some strong signs and good poise over his 10 games as a rookie and needs to add a little size to his frame this coming year.
Phil Davis: Limited by a back injury last season, Davis will be keen to re-establish himself as the Giants' fullback and the mainstay of the backline in 2014.
Sam Frost: Blessed with plenty of athletic gifts, Frost has been used in a variety of positions and has spent the pre-season down back. With Tim Mohr sidelined, an opportunity awaits to add to his five career games.
Tim Golds: It's an important time for the third-year defender, who has played three games to date and is running well during pre-season training.
Curtly Hampton: Benefiting enormously from the arrival of Heath Shaw and Josh Hunt, the gifted Hampton is performing well in training and looks set for another step up this year.
Nick Haynes: A young Giant that really stepped up over the back half of last year, the athletic Haynes appears set for a big season ahead as he stamps himself as a regular member of the back six.
Josh Hunt: Eased into the pre-season after another long campaign with Geelong, the veteran adds some bulk and that famous long kick into the young backline.
Adam Kennedy: Another young defender learning from Shaw and Hunt's tutelage, he has put on some size and is developing into an important small defender.
Tim Mohr: GWS' most consistent defender last season, a training mishap left Mohr with a foot fracture and in a moon boot and he will miss the opening few rounds of the year.
Lachie Plowman: The third pick in the 2012 NAB AFL Draft, the talldefender played six games over the opening half of the year before spending some time in the midfield in the NEAFL. But key defence is his position and he has put on some size in the off-season.
Heath Shaw: Another to slot straight into the leadership group, Shaw is focused and dedicated on being a good example for his young teammates on and off the field.
Zac Williams: One of GWS' real surprise packets of 2013, the speedy small defender has moved all the way from the Giants' academy to a spot on the senior list. One to watch. - James Dampney