Opposing styles: Magpie ruckman Darren Jolly has problems with the leaping style of the Eagles' Nic Naitanui. Photo: Sebastian Costanzo
THEY are one and three on the ladder and as likely as any pair of teams to find themselves facing one another in the grand final.
So what are the issues for the Eagles and Pies?
The ruck dilemma - what to do about Cox and Naitanui?
This isn't a Collingwood problem, it is a weekly football problem. Still, it looms as match defining.
Nic Naitanui had a career-high 25 possessions and 31 hitouts last week, including the effortlessly spectacular highlight he manages each week - a shot at goal that had it been on target would have rivalled Buddy's run for the sort of display that re-calibrates the parameters of the idea of the possible on the football field.
Collingwood has no one to go with Naitanui, for the simple fact that no one has someone to go with Naitanui.
The tag-team with Dean Cox means there is no respite in the middle and raises the idea of whether an opponent likewise requires two elite rucks. The answer would be yes - if you had two elite rucks of similar style. Collingwood don't.
Cameron Wood could play along with Jolly but is extremely unlikely to do so. Nathan Buckley said pre-season he favoured one ruck and the evidence of his sides to date is that he is true to his word.
So they will likely go with their preferred mix of Darren Jolly with Chris Dawes cameos. By his admission Jolly prefers to body against a ruck and wrestle, and dislikes the players who play a game the opposite of his, such as the high-leaping Naitanui. The fact of Ben Reid coming back into the side adds flexibility to the other Collingwood talls, but also means they would be even more loath to add an additional ruck such as Wood to the mix and thus reduce their quota of running players.
How will Collingwood handle Ben Reid, Nathan Brown and Chris Tarrant playing together?
Incredibly this will be the first time Collingwood has had this problem since they recruited Chris Tarrant back to the club. It was mooted as a problem when he was brought back, but was made to look like prudent list management as key defenders suffered long-term injuries.
Against West Coast, even a West Coast without Josh Kennedy, the three tall defenders is not the burden it could be against others. A likely mix works with Tarrant going to Darling, Reid to Lynch and Brown minding the resting ruck Cox or Naitanui.
What about the other end of the ground?
West Coast will lack for Will Schofield's run but normally look to Eric Mackenzie to Travis Cloke and Darren Glass on Chris Dawes.
What about Luke Shuey?
The world saw the hit Luke Shuey took to the ribs against Carlton on national television. It is a tough argument to convince that he plays, but if he does he would be very tender.
Who does Scott Selwood shut down?
Last week on Chris Judd was the model of what a coach could ask of a tagger - stop one of the best players in the competition and hold him to a game among the worst of his career (12 touches) and get it 33 times yourself.
He had a bit of help from his big brother but it was a hell of an effort.
This week's choice of opponent is narrowed by Scott Pendlebury remaining out with his fractured leg.
So Dane Swan would be the obvious choice to tag, though the thought might be entertained of tasking him to Steele Sidebottom.
The young midfielder has a Kade Simpson-like ability to wound sides with his run while attention is focused on others.
Dale Thomas would be the other obvious thought, but Thomas himself has been given the head-to-head tag roles lately so the question could as easily be asked of Thomas:
Does Daisy go head-to-head with Kerr, Priddis or Shuey?
The answer would likely be probably not. Strictly inside players are not Thomas' preference. He needs to be used in a role that allows him to spread and not be sucked inside the packs for too long.
Winning in Melbourne?
This is the legitimacy test for West Coast. They have a lengthy injury list and have yet kept winning so they are a team demanding respect.
But they still need to erase the asterisk against them sitting on top of the ladder that they must win against good sides in Melbourne.
This is the classic eight-point game in football and for teams vying for home finals where the difference between hosting and visiting is so dramatically different the result becomes incredibly important.