Collingwood coach Mick Malthouse said he never had any doubts that full- forward John Anthony would convert what proved to be the match-winning goal in Saturday's thrilling semi-final victory over Adelaide.

With his team trailing by one point, Anthony put the ball straight through the middle from 30 metres out on a slight angle after winning a contentious free kick for being held by Crows full-back Ben Rutten in a marking contest.

The goal, scored with just 20 seconds left on the clock, secured the Magpies a famous five-point victory and a date with Geelong in next Saturday night's preliminary final.

Anthony's match-winning moment capped off an otherwise dirty night for the 21-year-old who was held to just four touches for the night and for whom that crucial final goal was his only goal.

"That's their job - I thought Jack could knock it over," said Malthouse with a shrug at his post-match media conference.

"I was quite comfortable that Jack had it, barring a total kick into the man."

"I didn't want to go through those drawn finals again - we've already had one and we didn't need it."

Malthouse declined to buy into the debate about the merits of Anthony's free and was sparing in his analysis about what sparked the third-quarter turnaround when the Magpies slammed in six goals-to-nil to turn a 26-point half-time deficit into a 10-point lead at the final change.

"We were getting beaten in two areas that we needed to address ... and I'm not going to go through them with you, but the two things we needed to fix relayed the pressure back and gave us the chance to reverse the score," was all that Malthouse was prepared to share.

He was much more expansive on the matter of the benefits that would flow from the victory for his youngsters in particular.

"Finals football is on a big stage and there's no room in sides going forward for players who can't perform on a big stage," Malthouse said.

"(Steele) Sidebottom, (Brent) Macaffer, (Brad) Dick, (Cameron) Wood, to name some young players, ticked the boxes under pressure today - that's so important."

"You can do a lot of things in life but we are the biggest knockers and if someone can't perform in the big games, we label them and I don't think any of the boys wanted to be labelled as someone who couldn't perform at that level."

"Those boys stood up, just terrific for us."

Malthouse said he would weigh-up the week ahead and factor-in the form and selection prospects of a host of players in the VFL who enjoyed a semi-final win of their own against Williamstown on Saturday.

His priority, he said, is to pick the side best equipped to take on Geelong.

"We know it was a terrific win and it gets us to a preliminary final," he said.

"You don't get to a preliminary final unless you do things right and we did enough things right tonight against a terrific football side to challenge Geelong next week."

"And challenge them, we will."