Exeter have lost the services of flanker Julian Salvi for the rest of the year due to a bicep injury.
The 31-year-old Australian picked up the injury during the Chiefs' narrow Champions Cup loss to Ulster and needs surgery.
Salvi joined the Chiefs in the summer of 2015 from Leicester and became a key part of the side that made last season's Premiership final.
"We're still waiting to learn the full extent of it but it looks relatively serious," head coach Rob Baxter told BBC Sport.
"He does put in a huge contribution over 80 minutes, and that's probably what we'll miss the most. His biggest quality is his consistency. He turns up every week, and even when we've had some poor performances and even when some individuals within the side have played poorly, Julian's contribution has always been absolutely first rate," added Baxter.
"He's virtually always our top tackler, virtually always our top clearout guy, and probably the thing that people don't appreciate about him is how important he is to our attack.
"A lot of people talk about open-sides as being tacklers and defenders and disruptive people, but Julian is very important to our attack because he clears so many breakdowns."