ST KILDA is resigned to losing gun midfielder David Armitage for an extended period with groin issues.

The 28-year-old pulled up sore following last Sunday's round four win over Collingwood, and coach Alan Richardson said while ball magnet would definitely miss Sunday's clash with Geelong, there was a possibility he could be sidelined for much longer.

"He's still pulling up really sore after games, he'll have to have some tests," Richardson said on Friday.

"It looks like he'll miss a bit of footy, unfortunately.

"It looks like he's going need to possibly have corrective surgery, but if not, at least an extended rest to make sure we get it right."

Richardson disputed a suggestion playing Armitage against the Magpies did further damage to his troublesome groin.

While Armitage's injury is a big blow to the Saints' midfield, the coach was excited by the return from injury of three-time best and fairest Jack Steven.

The 27-year-old has missed the past two weeks with a punctured lung sustained in the round two loss to West Coast, and the star midfielder will be required to help negate the influence of the Cats' dynamic duo of Patrick Dangerfield and Joel Selwood.

"It's brilliant to have Jack back in the team," he said.

"He's a very dynamic midfielder with his combination of his inside work and his outside work."

Richardson conceded ruckman Tom Hickey would have been dropped even though he "pulled up stiff" from last week's game.

Billy Longer will replace Hickey and play his first game for the season after strong form in the JLT Community Series.

"We would have made the change, we think we've been on the back foot too much at stoppages, " Richardson said.

"We think 'Hick' has some room to move there in terms of being better for us in the ruck.

"But it's time for Billy to have a go, he was really positive in the JLT series, (and) he's had to wait and be patient.

"We're excited about what he might be able to do for our team."