THE MESSAGE for Saturday's Grand Final could be a simple one: Shop early.

Ahead of this year's decider between Sydney and Brisbane, AFL.com.au has teamed up with Champion Data to dive through the numbers and assess the five crucial areas where the season's biggest game could be won or lost.

Can the Swans be stopped through the corridor? What happens if the Lions control the tempo? And could it be as simple as whoever starts the fastest might be crowned premiers?

GET THE JUMP

Somewhat remarkably, 22 of the last 23 times a side has been leading the Grand Final at three-quarter time, they have gone on to win. It's a particularly crucial fact for this season's decider, which sees the notoriously slow-starting Swans come up against the red-hot Lions. Throughout the home and away season, Sydney was -135 in first quarters. It ranked John Longmire's side as the fourth-worst opening quarter side in the competition. Conversely, Brisbane was +297 in first terms this year, making the Lions the fastest starting side in the League. That stat might be negated slightly by Brisbane being -40 in final quarters this year, with Sydney being +100 in last terms. However, history shows comebacks in Grand Finals are more unlikely. The script has been slightly flipped this September, where Brisbane has been forced to overturn deficits of 44 points and 25 points to defeat Greater Western Sydney and Geelong respectively. For the knowledge buffs, Geelong's 2009 team remains the only side to overturn a three-quarter time deficit in a Grand Final dating back to the turn of the century.

KEEP CONTROL

Sydney can't allow Brisbane to control the tempo of the match. Chris Fagan's side loves to dictate the contest and dominate the play through uncontested marks, with its average of 98 per game across the season ranking as the highest of any side in the entire competition. The Lions have also won 11 of the 12 games this year where they've registered more than 100 uncontested marks, including last Saturday night when they overcame the Cats in the preliminary final having finished 100-56 for uncontested grabs. It was a similar story when Brisbane met Sydney at the Gabba back in July, where the Lions won by two points having led the uncontested marks statistic 107-86. If you allow the Lions the footy, they will make you pay.

KEEP THE SWANS WIDE

If Sydney can't let Brisbane control the footy, Brisbane can't let Sydney change angles in possession. The Lions did brilliantly keeping the Swans wide when they met back in round 19 and must try doing it again. Sydney kicked long down the line 22 times in that fixture, a season-high for Longmire's side. It's resulted in a trend, with more opposition teams attempting to force the Swans wide. Previously, Sydney had averaged 11 long down-the-line kicks per game which was the third fewest in the League. But since they faced Brisbane earlier this year, they have averaged 17 which is the second most in the competition. It's seen the side's inside 50s average dip from 56 per game (third most) to 48 per game (fourth fewest) and their retention rate going inside 50 drop from 53 per cent (the highest in the AFL) to 46 per cent (ranked No.10 in the League). If you deny Sydney the corridor, you can deny the Swans scoring opportunities.

WAYWARD LIONS

Sydney is the most accurate side in the game, but Brisbane is far from that. Across the season, the Swans notched 188 points more than their Expected Score (a metric to define the quality of a side's scoring opportunities). It was the highest figure of any team across the whole competition. The Lions, meanwhile, scored 89 points fewer than their Expected Score which ranked as the third worst in the League. That's across the entire season, but drill down into the last six weeks and the number becomes even more stark. Sydney is +17 per game compared to its Expected Score throughout that stretch, more than double any other side in the competition. Brisbane is -11 per game across that period, which is clearly the lowest number of any team. The Lions have also recorded a shot-at-goal accuracy of 47 per cent throughout the year, which ranks Chris Fagan's side as the fourth most inaccurate team in the League. They'll hope missed opportunities don't come back to haunt them again on Saturday.

TURN IT OVER, WIN THE GAME

It might sound simple, but whoever wins the turnover game on Saturday could win the premiership. The stats prove it. Firstly, 17 of the last 18 premiers after this weekend would have ranked top three in the League for points from turnover differential (the 2016 Western Bulldogs are the outlier, ranking seventh). Furthermore, all eight finals this season have been won by the team that outscored their opponent from turnover. Sydney and Brisbane are the best two teams in the entire competition this season for scoring from turnover. The Lions rank No.1 with a differential of +13 points per game, while the Swans rank No.2 with a differential of +11 points per game. Brisbane will feel confident in this regard, given it outscored Sydney from turnover by 28 points when they met in round 19. At the time, it was clearly the most the Swans had conceded from turnover all season.