ST KILDA coach Alan Richardson is hopeful the AFL has not seen the last of Leigh Montagna, but concedes the veteran on-baller's future is uncertain after a hamstring injury. 

Montagna limped from the SCG during the third quarter of the Saints' 42-point loss to Sydney on Saturday night.

Click here for full match details and stats

Richardson said it was a case of "wait and see" for the 33-year-old, who will have scans to determine the extent of the injury he picked up after being tackled. 

"Clearly he couldn't come back on the ground," Richardson said.

"He wasn't going to be able to contribute at all so he sat it out." 

WATCH: Alan Richardson's full post-match press conference

Montagna is out of contract at the end of this season, and while he has not made an announcement about his future, Richardson's rhetoric suggests retirement is a possibility.

TALKING POINTS: Sydney v St Kilda

There are only five home-and-away rounds remaining in 2017, although St Kilda remains a finals chance. 

When asked if he was hopeful about Montagna's prospects of playing again, Richardson said: "Yeah, we are."

"They're always a tricky one (hamstrings). You've just got to get all the evidence and do the scans.

"He's been in pretty good shape for us, so we'll just have to wait." 

Montagna is not the only Saints stalwart under a cloud, with Richardson confirming Nick Riewoldt would likely be rested for next Saturday's away clash against Port Adelaide. 

Riewoldt, 34, had a quiet night with only 10 possessions and four marks, but did kick a goal. 

"It was planned that 'Rooey' would either miss this one or next," Richardson said.

"We've had a couple of six-day breaks in a row, a trip to Perth, now a trip to here (Sydney) but we've had eight days between our last performance and this one.

"There's a chance that he'll miss but we'll just have to wait and see how he's pulled up and what our conditioning and medical people think." 

After a disastrous defeat to the Bombers in round 17, Richardson made five changes to his side for Saturday night's trip to the Harbour City. 

On a disappointing night for the Saints, one of those inclusions, Luke Dunstan, provided a bright spot with 29 touches, seven marks and nine inside-50s.