The unavailability of Lachlan Keeffe and Josh Thomas for Collingwood's season opener against the Brisbane Lions at the Gabba on Saturday night represents significant opportunities for the club's younger players, coach Nathan Buckley says.

Keeffe and Thomas have been provisionally suspended under AFL rules until they receive the results to their B-sample test on April 14 after returning a positive A-sample reading to performance-enhancing drug clenbuterol.

Keeffe's absence will impact the Magpies more from a longer-term point of view, given he has not yet recovered from a hamstring injury in time for the match against the Lions.

NEWS: No talks set for Pies pair.

Buckley, though, confirmed on Tuesday that Thomas would have been selected for the game against the Lions.

The Magpies will need to cover the losses of both Thomas and the injured Levi Greenwood, who is set to miss up to months with a hairline fracture in his ankle, through the middle of the ground.

Buckley said there were a number of players leading the charge based on their pre-season form.

"Tim Broomhead stood up against Richmond (in a VFL practice match last Thursday). We played 24 players against the Bulldogs (in the NAB Challenge), we still need to drop a couple off there," Buckley said.

WATCH: Buckley speaks on AFL360.

"Patty Karnezis has been really solid throughout, Paul Seedsman is coming up and thereabouts, Jordan De Goey performed really well against Richmond last Thursday, Ben Kennedy as well.

listen to ‘Press Conference: Nathan Buckley’ on audioBoom

"Don't worry - we don't have a shortage of hungry players that are ready to take that mantle and take that opportunity."

listen to ‘Press Conference: Nathan Buckley’ on audioBoom

Collingwood's engine room will also be boosted with the news that recruit Jack Crisp has been cleared to play after being fined $5000 for a bet he placed on the AFL during his time at the Brisbane Lions.

"It's probably best case scenario for Crispy. Once again, all the education in the world, but a poor decision," Buckley said.

Players were "absolutely flabbergasted": Eddie McGuire.

"Jack has gone about his business here fantastically. He is a hard worker, no fuss, head down, bum up and gets the job done. He is embarrassed about it but he is happy to have it at the other side of him."

However defender Ben Reid is not yet ready to play, according to Buckley.

"He's still going to need more game time," Buckley said.

"As we've said all along, we're not going to rush Ben back before his time.

"When we roll him out on to the AFL arena, not only will he be physically robust and ready to go, but he'll be in good form because he's going to have to push back past a few of mates to get in there."