England back Jack Nowell suffered a knee injury during Exeter's win over Gloucester at Sandy Park.
Nowell would appear to be a certain addition in Eddie Jones' first England squad, announced on Wednesday, but will now be monitored after his knock.
The 22-year-old went off towards the end of Saturday's Premiership win and Exeter assistant coach Ali Hepher said that every pre-caution would be taken regarding Nowell's fitness.
Jones has already lost another England winger in Jonny May to injury for the season.
Hepher said: "It's a bit of a twist of his knee. Unfortunately he has got twisted between two bodies and had to come off so we will wait and see.
"You don't know with these knee injuries and sometimes the least painful ones can be the longest out.
"So we will obviously get him assessed in the week."