Exeter winger Jack Nowell may miss the rest of the regular season after spraining medial knee ligaments.
The 28-year-old hobbled off after 53 minutes of Saturday's win over Worcester.
"It's a bit of a crippling blow for him seeing as he only just got back fit," said Exeter boss Rob Baxter
"Hopefully this won't be the end of his season and we'll see him before the end," Baxter added to BBC Radio Devon..
Nowell's lack of action this season - he missed England's Autumn Nations Cup and the Six Nations campaigns - contributed to him missing out on a place in the British and Irish Lions summer tour to South Africa.
Nowell was the first-ever Exeter player to get a call-up when he was picked for the 2017 tour to New Zealand and featured in the final two Tests.
"He was pretty distraught straight after the game, but he's a real positive character and he's one of these guys that look at the positive as soon as he can," Baxter said.
"All he's focused on now is getting himself fit and available for possible late-season games.
"He's brilliant like that and he's come through those situations well in the past and we're going to give him every opportunity to hopefully have some more input in our season."