ST KILDA will consider using returning skipper Jarryn Geary in another defensive forward role to quell the influence of Blues co-captain Sam Docherty on Thursday night.

Geary is a certain starter after missing two matches with a minor hamstring strain sustained when tagging speedster Jason Johannisen in the round two win over the Western Bulldogs.

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Docherty had a game-high 32 disposals in the Blues' win over Essendon last week, and will be a crucial cog to stop in the match at Marvel Stadium, brought forward two days from the scheduled Saturday slot due to the fixture flip.

Given the settled Saints' backline that kept Richmond to 10 goals in last week's win, coach Brett Ratten will contemplate team balance at selection on Wednesday afternoon.

"We've got to have a look at where he sits for us," Ratten said of his captain on Wednesday morning.

"We thought it (tagging Johannisen) was a strategy we thought would work on the day. Docherty's a different player to JJ, so does that work? I'm not sure.

"We'll go through that with finer detail after this training session."

Geary was one of 21 players to train in red jumpers at RSEA Park on Wednesday morning in an AFL group that looks set to tackle the Blues.

It included Jade Gresham, given the green light to play from an eye injury, and fringe players Dean Kent, Jonathon Marsh and Nick Coffield.

Recruit Zak Jones wasn't part of the group, restricted to running light laps as he battles hamstring tightness sustained in the win over the Tigers.

"It (shorter break) probably doesn't help Jones, that was going to be 50-50 and now it'll probably be 30-70 the other way," Ratten said.

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"Geary will be fine, he'll play, but Jones is the one with the risk versus reward, that will be the talking point (at selection) post-training. He's not going to do a lot (at training), but we'll sit down with the doctors before we select him.

"We'll probably err on the side of being cautious because it's a long season and a hamstring could turn into two, three or four (weeks)."

When the VFL squad departed for the outside oval during Wednesday's session, Jack Sinclair, Ryan Byrnes, Nick Hind, Paddy Ryder and Dylan Roberton – players who didn't play against the Tigers – continued to train on the main oval in yellow jumpers.

Josh Battle was also in a yellow jumper and could retain his place should Jones be officially ruled out when teams are announced on Wednesday night.

Midfielder Dan Hannebery left the track midway through Wednesday's session, but finished the session with teammates.

Ratten admitted the 60-minute hitout was longer than a normal Captain's Run the day before a match given the reduced week following a five-day break.