England centre Ben Te'o may miss the autumn internationals with an ankle injury that will keep him sidelined for at least a month.
Te'o limped off in the early stages of Worcester Warriors' win over Brive on Saturday and could be set for a longer spell on the sidelines if he needs an operation.
Warriors head coach Carl Hogg told the Worcester News: "He's being assessed currently and will head back down to Cardiff on Monday to see whether he'll go down a surgical route or whether it'll be managed conservatively.
"He's expected to be out for at least a month but we'll find out more next week once the swelling has settled down and it'll give us a better idea of timeframes."
The 30-year-old has won eight caps for England and impressed for the British and Irish Lions during their series against the All Blacks earlier this year.
England have three matches lined up next month. They play Argentina on November 11 and face Australia a week later. That is followed by a game against Samoa on November 25.
England are already missing another centre Manu Tuilagi for the three tests, but he could be back in action in early December following knee surgery.