St Kilda champion Nick Riewoldt suffered what initally appeared to be a serious knee injury during the final term of the Saints' clash with Melbourne at Etihad Stadium.

Riewoldt landed awkwardly in a marking contest and clutched at his knee before he was taken from the ground on a stretcher.

However, following the match, St Kilda said the injury does not look as bad as initially feared.

"I heard a big pop and there was pain and I reacted to it," Riewoldt told Fox Footy post-match.

"I thought that (ACL) was what I'd done.

"The docs are pretty happy with the testing that they've done be that it's not ACL but there's clearly something in there."It's stiff and sore now. Gave it a pretty good wrench."

Riewoldt will undergo scans on Sunday.