THREE things happened last weekend, all linked to the same game, which might have an impact on the top-end of November's NAB AFL Draft, and the trade period that comes before it.

Greater Western Sydney beat Melbourne, pushing it a game clear of the Demons on the ladder. It lost Jonathon Patton to a second knee reconstruction, which will see him miss most of next season. And then the Demons applied for a priority pick, one unlikely to be granted but a question worth asking, forgetting the timing.   

All of that could influence how things play out in the exchange and draft period.

The top end of this year's draft – and the draft pool on the whole – has been viewed as the most even in years by clubs. But a general consensus has developed among recruiters around the leading four players available of the draft crop. 

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Christian Petracca has elevated himself to be the number one player in many eyes, such has been his consistent season in the midfield and dominance there. Paddy McCartin is the best pure tall forward, who collects plenty of marks and shots on goal each week.

Peter Wright is 203cm and can play as a forward and a ruck, and Angus Brayshaw's early-season form pushed him up the order and he's stayed there throughout the year.

Although clearly a couple of prospects could emerge as top-four picks outside these names, it is unlikely any of Petracca, McCartin, Wright and Brayshaw won't feature in the first handful of selections.  

Which leads us to St Kilda, Melbourne, the Giants and the Brisbane Lions, who occupy the last four spots on the ladder. Each of the four brings respective qualities that are attractive to those clubs – and many others.

St Kilda has indicated it will take the best player, regardless of size and shape. They need a young key forward and McCartin is that, and the only thing that's been able to stop him this year is a couple of niggling injuries.  

Nothing has stopped Petracca, but something to be considered is the fact the next two drafts – at this stage – look to be filled with more midfielders than talls in the early part.

Greater Western Sydney's strategy in the past has been to take the best talls when they're available, including Tom Boyd, Cameron McCarthy, Lachie Plowman, Aidan Corr, Kristian Jaksch and James Stewart as top-30 selections over the past two drafts.

Before Patton's injury last week, most felt Petracca or Brayshaw, or some other pacy options, might best fit their needs.

But it has left rivals wondering about what the Giants do next.

The whispers about Patton returning to Victoria, or the Saints offering pick one for Boyd, had spread quickly. But Patton has extended his contract through to the end of 2017, and his knee means even more importance will be placed on securing Boyd to a similar commitment.   

The luxury of talls brings with it another factor: fitting them all in.

Of their two recent drafts, Corr, Plowman and Stewart have had limited opportunities, McCarthy hasn't debuted yet and Jaksch will in the next two weeks tell the club if he is staying beyond this season or requesting a trade back to Victoria. 

Paul Roos has signalled the Demons' intention to add midfielders to their list, and Petracca and Brayshaw both have the mature bodies ready to step into top-level football.

Melbourne's bid for a priority pick has been deemed more likely to fail than not, but if granted, does not necessarily need to come after their first selection. It could come at the end of the first or second round, or with a caveat, such as the condition they have to trade it.

The compensation pick that may come their way if free agent James Frawley departs the club would be another factor to change things, particularly if it gave them another top-five selection. That, again, would change the machinations for what happens at the start of the draft.

The Lions, currently 15th on the ladder, will be forced to wait and see who gets through to them – much like they have done the last two years with Sam Mayes and James Aish.

Not so long ago, they were looking the likely destination of pick one. But they are playing with spirit and conviction, built on the youth they have brought into the club. They have drafted well, improved their welfare department, and shown things can get better, quickly.

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