Magpie swingman Ben Reid is a confirmed starter for Saturday’s vital clash with Adelaide, subject to completing Friday’s training session.

Reid is set to return after having most of his season ruined by calf and quad problems.

He has played the past two VFL games, has been back training for six weeks and Collingwood coach Nathan Buckley said Reid was ready to play.

"He's important for our structure," Buckley said. "But he is only one player."

After spending most of the season pitching Reid as a forward option, Buckley said circumstances meant the Magpies were considering playing him in defence against the Crows.

The 25-year-old kicked 25 goals in 2013 as the second tall forward but played in a premiership and earned All-Australian selection as a defender.

The Crows have three tall forwards - Taylor Walker, James Podsiadly and Josh Jenkins - who have kicked 60 goals between them and pose a threat to a Magpie defence that will miss the recently retired Nick Maxwell.

"Whether we use him (Reid) forward or back will depend on the make up of the squad," Buckley said. "It's a definitely a consideration."

The Magpies must make at least two changes with Maxwell retired and Dane Swan injured, meaning Collingwood will enter a game without one of the pair for the first time since round 12, 2006.

The Pies are certain to select Jamie Elliott for his 50th game, but Buckley was non-committal as to whether more changes were necessary after the 63-point loss to Essendon before the bye.

He said the make-up of the team would be determined by who can win contests and pressure the opposition, something he said had been lacking recently.

"The one thing that we haven't been getting right is the contest, and that sets up the other two (defence and offence). So if you boil it down, it's the ability to pressure the opposition at the contest, and the ability to win the ball at the contest," Buckley said.

Collingwood has lost four of its past five games and is likely to fall out of the eight if it loses to Adelaide.

"We need to find better form, we need individuals to be playing better footy and we need to be playing better collectively," Buckley said.