Geelong had to withdraw defender Tom Lonergan before their semi-final win over Sydney on Friday night due to food poisoning, and it seems as though one of his teammates have now joined him in the sick bed at the club.

First-year defender Tom Stewart has also fallen victim to an illness, with Channel Nine's Corey Norris suggesting the 24-year-old has been struck down with gastro.

Stewart confirmed the reports when he left the club on Monday, with he and Longeran being sent home just 15 minutes after arrival.

"Gastro, food poisoning ... one or the other, so hope I'll be right. I think it's just us two at the moment … bit of quarantine," Stewart told reporters as he left the club.

It isn't perfect preparation for Geelong, who face Adelaide in a preliminary final at the Adelaide Oval on Friday night, for a spot in the grand final.

However, the Crows haven't had a flawless week off either, with forward Mitch McGovern under his own injury cloud due to a hamstring injury.

McGovern "reported soreness in his hamstring" after a session over the weekend, and will be monitored throughout the week.