Sam Jones is expected to miss England's autumn internationals after breaking his right leg during a judo session.
The 24-year-old fractured his right fibula during the sessions, organised by head coach Eddie Jones, on Tuesday in Brighton and is awaiting an estimate on how long he faces on the sidelines.
Jones, who suffered the injury while grappling with Maro Itoje, is expected to miss the autumn Test series, which kicks off against South Africa on November 12, live on Sky Sports 1.
The Rugby Football Union had initially said Jones injured an ankle, but his Aviva Premiership side Wasps confirmed the fracture on Wednesday.
"The club is awaiting the results of subsequent MRI scans and Jones will see a specialist on Friday afternoon to determine the extent of the injury," the club's statement read.
Wasps rugby director Dai Young admitted his sympathy for Jones after performing so well this season, but insisted the club will be able to cope without him.
"It's a big blow and I really feel for Sam, because he has worked his socks off for Wasps and deservedly got his call-up to England," Young said.
"Sam has been one of the first names on my team sheet this season and he will be a big loss for us, but we are lucky to have a lot of talented back-rowers at the club who have already stepped up this season.
"My biggest disappointment is for Sam as he's been playing so well and I'm sure would have made a good impression in the England camp.
"These things happen, but you can't help but feel sorry for him. It's too soon to know how long he will be out, but our medics and physios will look after him and we look forward to having him back when he is ready."
England will host four matches at Twickenham Stadium, facing South Africa, Fiji, Argentina and Australia.