Exeter have suffered a blow with in-form second-row Mitch Lees ruled out for four months after having an operation on a biceps injury.
The 27-year-old, who was a possible call-up to England's squad for the upcoming Six Nations Championship, is now set for a long spell out.
"Mitch is going to be out long-term," head coach Rob Baxter told the club website.
"It is a blow but any team in the Premiership has to be able to weather these things and get on with it."
Baxter also revealed that scrum-half Will Chudley is unlikely to train this week after suffering minor ankle ligament damage on Saturday.