St Kilda have ruled out former captain Nick Riewoldt for their important clash with Adelaide at Adelaide Oval on Friday night.

The Age's Daniel Cherny confirmed the news on Monday afternoon.

Riewoldt had been battling knee issues all season, and was rested for his side's loss to the Western Bulldogs in round 10, a move coach Alan Richardson conceded he should have made earlier.

“He probably wasn’t at his best that game. Still did a reasonable job for us structurally, but didn’t have a great influence on the game,” Richardson told the media on the eve of the Bulldogs fixture.

“In hindsight, we possibly could have rested him then."

This Friday's game against Adelaide will be the third game Riewoldt has missed in 2017, after missing just one for the entire 2016 season.