SATURDAY night at Etihad Stadium marked the end of the audition period and now, Hawks coach Alastair Clarkson must decide who the new cast members will be for the 2016 production of Hawthorn, the Four-peat.

At this stage, there are four vacancies in the team that beat West Coast in last year's Grand Final.

Just to recap, Brian Lake and David Hale have retired, Matt Suckling took the free agency route to the Western Bulldogs and Jarryd Roughead's PCL reconstruction leaves him sidelined until the second half of the year.

There might yet be a fifth change needed. Midfielder Liam Shiels hurt his wrist in the final quarter of Saturday night's NAB Challenge hit-out against North and depending on the result of scans in the next day or two, might also be missing on Easter Monday against Geelong at the MCG.

So who steps in as the Hawks embark on their quest to become just the second team in League history to win four straight flags?

The absolute lock is ruckman Jon Ceglar who will be the direct swap for David Hale. Ceglar played his first match for the pre-season against the Kangaroos and after blowing hard in the first quarter, he found his groove and became one of the more influential players on the ground, particularly in the third term when the Hawks put the game away.

There were lengthy periods in the past two seasons when Ceglar was a fixture of Hawthorn's best 22 and he is stiff not to have at least one premiership medallion in his bedside drawer. The Hawks lose little with him in the side to replace Hale.

Brian Lake's departure leaves a void. The Hawks like the emerging 198cm key defender Kaiden Brand a lot, but only gave him a half against the Kangaroos, which suggests he is not quite the in the mix just yet. Brand didn't play at all last year because of a shoulder reconstruction and you'd think the Hawks will give him at least a few weeks at VFL level. That might change if the Cats load up with tall forwards as they did against the Dockers on the weekend.

Angus Litherland probably gets the nod, not so much as a direct replacement for Lake, but as part of a defensive back six that mixes and matches depending on the opposition. Litherland played 13 matches in 2014, but only six last year. But he understands Hawthorn's complex defensive system, can play small and tall and he's quick.

Angus Litherland looms as a good chance to play in round one. Picture: AFL Media

Pre-season football can be deceiving but on the basis of exposed form in the NAB Challenge, Daniel Howe might have earned himself a round one berth as the replacement for Suckling. In three games, the 191cm Howe has had 23 possessions and 12 marks, 14 and three and 15 and 10.

He doesn't have Suckling's exquisite kicking skills, but then again, who does? Nevertheless, Howe, who was introduced in four games last year, is a smart footballer, composed across half-back and already competent through the midfield.

Roughead is the player who will be missed the most even though Saturday night's 18-goal return suggests the Hawks can still tick the scoreboard over at a rapid rate. Clarkson has hinted at a smaller forward line in Roughead's absence and it was notable that skipper Luke Hodge rotated between the midfield and the forward line rather than his usual half-back during the half a match he played. 

Speedster Billy Hartung or the emerging medium forward James Sicily will likely get the nod against the Cats. Hartung was rested in the second half after a knock to the knee, while Sicily was lively after half-time.

If Shiels doesn't come up then both Hartung and Sicily figure to play on Easter Monday, which thanks to the AFL's 'six-six-six' fixturing arrangement, is the only time the great modern rivals will play for the year.

Hawthorn's quest for a fourth straight flag will be one of the over-arching stories of the season. The added twist is that the Hawks will be chasing history while at the same time undertaking a gradual rebuild of their list, which begins in earnest in a fortnight.

Let the match committee debates begin

Selection headaches abound at most clubs at this time of year with the season opener now on the immediate horizon.

What happens over the next fortnight at the Western Bulldogs will be most interesting. No.1 ruckman Will Minson likely won't play against Fremantle because of a hamstring strain, but the quandary is still there.

Some will depend on whether Tom Campbell overcomes a rolled ankle suffered against Collingwood on Saturday. Jordan Roughead was sent back to the VFL for a practice game on the weekend, primarily for the purpose of getting a full game under his belt, but he remains in the frame for round one.

Then there is the Tom Boyd versus Jack Redpath battle. Based on the end of last season and even through the pre-season, the less-heralded Redpath might have been the more likely round one starter of the pair.

But Boyd was prominent against Collingwood on Saturday, with a couple of great contested marks and he was effective in the ruck. By virtue of his mega contract, Boyd will be one the most scrutinised players in the competition this year and every game he misses for reasons of form and team balance will create some sort of headline.

Coaches are grappling with how to structure up this year with the substitute gone and four players on the bench rotating up to 90 times. The general theory is that it makes two ruckmen sustainable for all teams, as long as at least one of them can add something to the forward mix.

Bulldogs coach Luke Beveridge is flagging the possibility of three big men. Even without Minson, he has four in play and he will be up against the Dockers in round one, who will be without Aaron Sandilands. Oh, to be a fly on the wall at match committee.

Tom Campbell's sore ankle has added to the Dogs' selection headaches. Picture: AFL Media

Three games, two games or none?

This time last week we expressed satisfaction that the NAB Challenge format seemed to be working. But perhaps we spoke too soon.

The last few minutes of Thursday's Richmond-Port Adelaide game ended in farce as the Tigers kept taking players off the ground as the injury toll started to mount, and after an unsuccessful plea to the AFL to call the game off. At one stage, there were just 15 Richmond players on the ground.

Tigers obliged to play the game out: AFL

Port coach Ken Hinkley then said two pre-season games were plenty enough in his opinion.

And AFL football operations manager Mark Evans said the League would listen to the clubs and if they wanted no games whatsoever, then that is on the table.

Except that it might not be. The fine-print of the AFL's new TV rights agreement, which kicks into gear in 2017, calls for a minimum of 12 pre-season games each year.

What cannot be disputed is that teams need pre-season games and not just between themselves. Players need proper body contact, structures need to be tested, and new and developing players need to be exposed.

A few years back, when the final weekend of NAB Challenge games were not televised, you had matches such as one between the Hawks and the Kangaroos at Craigieburn that was called off in the final quarter when monsoonal conditions set in. With no TV cameras and importantly, no wagering on the game, Clarkson and Brad Scott could shake hands and send the players off for an early shower.

But the stakes are higher when fans are paying up to $30 for admission, more than 100,000 people are watching on TV and presumably, a fair bit of money is wagered.

That's when integrity comes into play and with it that the full 80 minutes (plus time-on) be played.

If the 18 senior coaches want to effect changes, then the AFL will be listening. Presumably it will be on the agenda when they meet the AFL's leadership this week in Melbourne ahead of the season launch activities. 

Damien Hardwick wasn't happy late in Thursday's NAB Challenge game. Picture: AFL Media

Notable mentions

1. Remember when Paul Roos took next to no interest in the pre-season competition when his Sydney Swans were ruling the roost? So how does he feel now after a NAB Challenge series where his Demons went through without a loss and gave every sign of serious improvement. Hard at the footy and quick with the ball, Melbourne has been enjoyable to watch this summer and already appear to have done well with tough midfielder Clayton Oliver, taken with the fourth pick overall at last year's national draft. Add Angus Brayshaw, Heritier Lumumba, Chris Dawes, Lynden Dunn, Aaron vandenBerg and Christian Petracca to that side, and the Demons should approach the new season with excitement and confidence. 

2. Twenty-six disposals, four clearances and two goals. That represents a nice first official outing by Adam Treloar for Collingwood. Bart Cummings didn't prepare his Melbourne Cup horses as meticulously as the Pies have Treloar and he will look forward to returning to his old city – if not his old stamping ground – for the season opener in a fortnight.

3. North Melbourne was disappointing in large parts against the Hawks, particularly after half-time, but Daniel Wells is exempted from that. He led the Kangas with 24 touches, regularly found space and the silky skills were in evidence. North needs him to fire and if so, the rest of the competition can sit back and enjoy.

4. Not sure what Jeremy Cameron and Dayne Zorko were thinking with their reports within a minute of each other at Metricon Stadium on Sunday. The Lions will struggle to get near West Coast even if Zorko does play, but Cameron's absence for the Giants in their season opener against Melbourne at the MCG tips the scales perhaps in favour of the Demons. Cameron left the ground and made contact to the head of Rhys Mathieson – a real no-no in the eyes of the Match Review Panel. If the Giants are to make the finals, they need to bank as many winnable away games as they can and that task might be about to become that bit more difficult without their best key forward.