Richmond AFL coach Damien Hardwick is confident defender Troy Chaplin will be able to play against St Kilda on Sunday – just a week after being carried off the ground with what appeared a nasty knee injury.

Key defender Chaplin wrenched his knee late in last weekend’s win over the Western Bulldogs.

The Tigers opted for caution, as Chaplin has previously had problems with the knee. They hope to be rewarded in time for Sunday’s MCG clash.

If Chaplin plays he would face in-form St Kilda skipper Nick Riewoldt.

“Troy we think is probably a 90-per-cent chance of playing, which is an outstanding result,” Hardwick said on Thursday.

“Our medical team have worked incredibly hard to get him up … people who have had knees before, your knee can at some stage slip.

“He had one of those episodes, and the scar tissue around it tweaked it a bit. There was minimal swelling. We think we dodged a bullet there.

“If he’s available this week, it would be an enormous result. He’s an important player coming up against a champion player.”

While Hardwick believes both tall defender David Astbury and youngster Nick Vlastuin have avoided serious injury from last weekend, both face fitness tests to determine whether they face at least a week off.

Astbury tweaked a hamstring against the Bulldogs, while Vlastuin suffered a bruised shin.