Exeter forward Dave Dennis has been ruled out for the rest of 2017 after injuring his bicep in training.
The 31-year-old, who is in his second season with the Chiefs, scored a try in the win against Wasps last month.
“He’s got a relatively serious injury, he’s had an operation. He’s likely to be out for 10-12 weeks,” Exeter boss Rob Baxter told BBC Radio Devon.
He is the latest in a number of senior Exeter players to be sidelined by injuries this season.
England and British and Irish Lions winger Jack Nowell may miss the autumn internationals after breaking his cheekbone, while fellow internationals Ollie Devoto and Luke Cowan-Dickie are also out.
The Chiefs are also without Dave Ewers, Sam Hill and Italy’s Michele Campagnaro.
The number of injuries in rugby union has come under the spotlight in recent weeks, with 82 players from 10 Premiership clubs ruled out ahead of last weekend’s fixtures.