SPECULATION surrounding experienced St Kilda defender Sean Dempster's relationship with the club has been quashed by coach Alan Richardson.

Dempster, 33, was surprisingly left out of the round one team that lost to the Demons by 30 points last Saturday. The omission came after he finished equal-10th in the club's best and fairest last year (with tough onballer David Armitage).

It has since emerged Dempster is dealing with a medical condition he does not want to share publicly, and is considering retirement from a 222-game career spanning 15 years with the Swans and Saints.

"What I would like to clear up is the speculation around an incredibly highly respected footballer at our footy club, almost getting overly disappointed with non-selection and giving the game away. It couldn't be any further from the truth," Richardson said at Melbourne airport on Friday.

"We're talking about a bloke that has bled for our footy club for a long time that needs to get some things sorted out. We'll give him the time to do that. There's no timeframe on that.

"He'll work with our medical staff closely in the next couple of weeks and hopefully then, when he sits down with his family and close friends, he can make a decision in the best interest of Sean Dempster and our footy club."

Richardson was reluctant to discuss the confidential nature of Dempster's condition.

"'Shinner's' dealing with some medical issues. It's between Sean and the doctor. I have an understanding of where that sits, but for personal reasons, we're not going to go any further with that," he said.

Asked before the side flew out to Perth to face West Coast on Saturday night whether he knew about the specifics of Dempster's case when picking the round one team, Richardson said he had not been completely informed at that stage.

"I didn't. He (Dempster) didn't get selected based on form," Richardson said.

"There is a chance his form, certainly in the last game, had been compromised by what he's dealing with now. But really, that is speculation."

Dempster featured in the Saints' first two JLT Community Series matches but played a VFL practice match as the rest of the team went up to Albury to face Sydney for the club's final pre-season game.

He copped a heavy hit from the Power's Nathan Krakouer in February, which saw Krakouer suspended for a game, but lined up against Carlton nine days later.

Dempster did not play for Sandringham last weekend.

Dempster has played in five Grand Finals, with his only success as part of the Swans team that defeated the Eagles by four points in 2005.