CARLTON coach Brendon Bolton has revealed he's "nervous" about the extent of a leg injury to promising youngster Zac Fisher.

One of the side's brightest prospects, Fisher limped from the field late in the first quarter after his leg turned in a tackle, with the Blues concerned about the possibility of a fracture.

"Fisher had a real heavy knock to his leg," Bolton said after the game.

"He's been hit really hard there. We'll have to scan that and see where that goes.

"I think it's more central in his leg than that low (the ankle). I'm a little bit nervous about that one, to be frank. I hope he's OK. He might have a fracture, but we don't know yet."

Fisher took no further part in the game and is set for scans in the coming days, with Carlton's injury issues compounded another disappointing performance.

Dale Thomas was withdrawn from the game on Saturday after a laceration to his knee failed to heal in time, while fellow defender Liam Jones also went down with a knock to his knee.

Like Fisher, Jones failed to complete the game, with the Blues playing the entire second half with just two players on the bench as the Hawks ran away 72-point winners.

Bolton revealed he didn't believe Jones suffered an ACL injury, having collided heavily with teammate Kade Simpson in a marking contest, but said he was worried about the issue.

"Jones has had a really heavy knock to his knee," Bolton said.

"Again, we'll have to scan that and see where that is. I don't think it's an ACL, but it could be any of the others. I'm just crossing my fingers that it's not significant.

"He's really tough, it takes a lot for him to go off the ground. If you don't play a game out, both with Fisher and Jones, you get pretty nervous that they're going to miss some games."