Source: ABC News

The Adelaide Crows may have to make a late change for the tomorrow night's clash against Fremantle at Football Park with young ruckman Shaun McKernan suffering an arm injury.

McKernan was injured at training on Friday and the Crows are waiting for a medical assessment.

Coach Neil Craig says emergencies are Robert Shirley, Richard Douglas and Jared Petrenko are among the options to replace McKernan.

"You know what our emergencies are, so it'll probably come from one of those," he said.

"If Shaun's ruled out earlier I think we can bring another emergency in, so we'll work our way through that - he's reasonably sore but we'll just have to sit and wait."

Meanwhile, Fremantle's assistant coach Barry Mitchell says the Dockers' young ruckmen will step up against Adelaide tomorrow night to cover the loss of Aaron Sandilands.

Sandilands will miss the match with hamstring soreness.

Mitchell says Fremantle will not be changing its game much.

"Obviously Aaron gets his hand on the ball a lot, so in some ways teams have been able to pick us off a little bit," he said.

"We go in with Zac Clarke this week - he's a developing ruckman and Keppler Bradley will back him up, so we try to do similar things with the midfield."