STAR Collingwood veteran Steele Sidebottom believes Billy Frampton can play an important role in crashing packs and creating contests after the versatile tall's unlikely call-up for the Toyota AFL Grand Final.

Magpies coach Craig McRae on Wednesday confirmed key forward Daniel McStay's replacement for Saturday's decider against Brisbane would be journeyman Frampton.

The former Adelaide and Port Adelaide utility, who arrived at the Magpies during the last off-season, has not played since round 24, being named as an emergency for Collingwood's finals victories over Melbourne and Greater Western Sydney.

"One of the big strengths of 'Chooka' Frampton is he's got that real aggression and I think that stands up in big games, guys that crack in," Sidebottom, who will play in his fifth Grand Final, said on Thursday.

"We're not expecting him to go out there and do too much.

"We just need him create a contest whether it's forward or back ... but it'd be nice if he did kick five (goals)."

Sidebottom is bitterly disappointed for McStay and midfielder Taylor Adams, who have been ruled out of the Grand Final.

McStay injured his knee after kicking two important goals in the preliminary final win over the Giants.

Adams was Collingwood's best player the last time the Magpies reached the decider in 2018 when they lost a thriller against West Coast.

But the 30-year-old effectively ruled himself out of contention after training on Tuesday, failing to overcome a hamstring strain suffered two weeks ago following the qualifying final victory over Melbourne.

"It's something that I'd hate to go through myself," Sidebottom said of the pair's plight.

"I guess for me as a mate of Tay's (Adams), it's just to help and support him.

"But for him to put the team ahead of himself ... he's a leader of this footy club and although he's not going to be out there on Saturday, he's still got a big role to play."

Thousands of supporters turned out for Collingwood's open training session at the AIA Centre on Thursday.

In the crowd were former Magpies heroes such as Anthony Rocca and Shane Wakelin, but also 1953 and 1958 premiership player Thorold Merrett, who turns 90 on Saturday.

"It's something that 'Fly's (McRae) good at is touching on our past, bringing a lot of our past players back in," Sidebottom said.

"We always look to our past and they're just as much a part of it as what we are."