UNDERMANNED Collingwood's eight-point win over West Coast could define the Magpies' season, veteran defender Nick Maxwell says.

The Pies clung on to keep their top-four hopes alive despite the loss of two key defenders before half time.

"It was a tough game and one of the best wins I've been a part of because all those key defenders are so important to us," Maxwell told AFL.com.au.

"Particularly for our young guys, it was almost like winning a final because they get the opportunity to have to play under huge pressure.

"The stats aren't going to be pretty but in the end, sometimes that happens.

"When you lose a couple of guys and you've just got to dig in and fight … that's what we did."

Backman Nathan Brown (shoulder) was subbed out at quarter-time. The blow was compounded by the loss of Jack Frost to concussion at the main break.

Alan Toovey stuck with Jack Darling and played an important role in keeping the big Eagle quiet while Tyson Goldsack had to play on Josh Kennedy, who stands 3cm taller and is 9kg heavier.

Maxwell also had to adjust from starting as the loose man in defence to lining up on the resting ruckman, with Dean Cox and Nic Naitanui rotating through the forward line.

With Tom Langdon continuing his remarkable first-season form and Clinton Young coming on as the sub to help Heritier Lumumba generate drive from defence, the Pies' backline stood strong.

"It was like just holding back the flood the whole time with the number of inside 50s they had," Maxwell said.

"Down back, guys were giving away 30kg and 30cm on those big guys.

"We knew they'd try and exploit it and they did because they're a quality team so we had to dig in.

"For our young guys to step up and win a lot of one on ones and 'Goldy' to continue to show us he can play multiple roles was just really important for us."

Maxwell said the win was better than his side's round-two victory over the Sydney Swans because of the heart they showed after the Eagles regained their three-quarter time lead midway through the final stanza.  

"We didn't have any rotations and we were all cramping in the end and it was pretty tough," he said.

"If we don't win that we fall further behind so it could be defining by the end of the season.

"We got the win and now we have to make sure we do the right thing again in six days' time."

The Pies face St Kilda in round 11 on Friday night at Etihad Stadium.

Meanwhile, coach Nathan Buckley praised the defenders for their performances and hailed Maxwell's game – 20 disposals, six tackles and four rebounds – as among the best in his 206-game career.  

"If 'Maxy' says that's in his top five wins, I would nearly say it is in his top five games for the club," Buckley said.

"I thought he was huge."

Twitter: @AFL_JenPhelan