Harry McKay in action during a Carlton training session at Ikon Park in January, 2021. Picture: AFL Photos

CARLTON expects key forward duo Harry McKay and Levi Casboult to be fit for Thursday night's season-opener, with the Blues readying a 23-man team in anticipation of the AFL introducing an injury sub on the eve of the clash.

The League confirmed on Wednesday that clubs will be allowed to name an additional player as a medical substitute during the season ahead, with Carlton having already prepared for that outcome.

Attacking duo McKay (ankle) and Casboult (knee) are expected to be part of that 23-man group, having both cleared fitness tests earlier this week after enduring injury setbacks in the lead-up to the clash.

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However, Casboult still trained away from the main group on Wednesday morning, while mystery surrounds Jack Martin's availability after he also watched on from the sidelines throughout the club's final session before game day.

Harry McKay walks off after Carlton's AAMI Community Series clash against St Kilda. Picture: AFL Photos

"They got through training on Monday," Carlton coach David Teague said.

"All of our players got through training well on Monday. It's just going to be how they've pulled up and whether they're able to. From all reports so far, it's all looking positive at the moment."

McKay and Casboult are likely to be joined by Jack Newnes in the team, after the wingman also cleared a fitness test following an ankle injury. Veteran forward Eddie Betts is fit following a calf problem, but is no guarantee to be named in the selected side.

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Running defender Adam Saad and small forward Lachie Fogarty will make their club debuts, having arrived at Ikon Park during last year's Trade Period, but midfielder Zac Williams will miss through suspension.

Eddie Betts running laps during a Carlton training session at Ikon Park on February 12, 2021. Picture: Getty Images

Carlton was informed of the AFL's plans to introduce a concussion substitute during the club's captain's run Wednesday, with the Blues keeping two players in mind for the fifth spot on their bench ahead of Thursday night's game.

"I'm guessing there's going to be another one," Teague said.
"We're still trying to get clarity on the rules and exactly what it is, then we'll make a decision. We've got it down to two (for that spot) at the moment, if it happens. They'll come into the group.

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"But we've got to get through training yet. We've got a few guys who have had some tests on Monday, they had yesterday off, so we need to make sure they've pulled up alright today before we finalise our side."