Stewart had to be substituted out of Friday night's loss to Collingwood at the MCG after injuring his right knee, with scans confirming he suffered a grade two medial collateral ligament (MCL) injury.
The Cats expected Stewart to only be sidelined for a short time.
"While disappointing Tom sustained an injury in last Friday night's game, following scans it was pleasing news the injury is not severe enough to keep sidelined long term," Geelong football boss Simon Lloyd told the club's website.
"We expect Tom to return to the line-up in the short term."
Defender Sam De Koning won't need to join Stewart on the sidelines and is due to take on older brother and Carlton ruck-forward Tom in Thursday night's match at the MCG.
The young gun left the field during the second quarter to have his knee assessed but returned to the field after half-time and played out the game.
"Sam was able to return to the field after being treated by our staff during the game, he has been assessed by our medical team and we expect him to train and be available for selection this week," Lloyd said.
When Stewart and De Koning were injured, they appeared to have trouble with their footing on the MCG playing surface, which was re-laid after the Ed Sheeran concerts earlier this month.
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