Exeter wing Jack Nowell faces weeks out of action after returning from England's training camp with a torn thigh.
The injury verdict was announced by Exeter director of rugby Rob Baxter after the Chiefs' 27-27 draw with Gloucester in the Aviva Premiership.
Nowell had been involved in the two-day camp at Brighton earlier in the week and becomes the third player to return from the session with a significant injury.
Wasps flanker Sam Jones broke his leg during a judo session while with England, and Bath wing Anthony Watson broke his jaw during a collision.
Baxter felt England had pushed Nowell too hard. The 23-year-old had only just returned to full fitness after a two-month injury lay-off, having needed thumb surgery.
The Exeter boss said: "Jack had a run-out with us last weekend and had his first bit of rugby. England seemed to have loaded him more than we would have done.
"We were told that the injury was minor but when we scanned him, he had a 9-10 centimetre tear in his quad which will put him out for weeks."
After the injuries to Jones and Watson came to light, Premiership Rugby on Thursday accused England head coach Eddie Jones of placing player welfare at risk by staging the full-bore training camp just days after a weekend programme of club fixtures.
It remains to be seen whether Nowell can return in time for England's autumn internationals, the first of which sees them face South Africa at Twickenham on November 12.
Baxter praised Exeter's efforts as they came back from 27-14 with 10 minutes remaining to hold Gloucester, thanks to a try from Damian Welch 30 seconds from the final whistle.
Two tries from Ian Whitten and one from Thomas Waldrom, together with Welch's effort, secured Exeter a bonus point. Gareth Steenson completed the scoring with a penalty and two conversions.
Baxter said: "The game was good, bad and ugly and we gave up some simple possession and points. We gave away two soft tries in the first half.
"The good part was our comeback as to score three times in the last 10 minutes was fantastic and those 10 minutes was probably the best we've played all season.
"We are not quite on our game; we carry out our game plans, show good character but need to step up a notch."
Despite the disappointment of not picking up a deserved win, Gloucester boss David Humphreys accepted it was an improved performance from his side.
They had stunned Exeter with some wholehearted aggressive tackling and were rewarded with tries from Matt Scott, Ben Morgan and Charlie Sharples.
Greig Laidlaw converted all three and kicked a penalty, with Billy Twelvetrees adding a long-range effort.
Humphreys said: "It was a big step up in intensity from us, which we needed to do against a strong side like Exeter.
"We played some very good stuff but careless errors let Exeter back into the game. We are pleased to get two points but incredibly frustrated at once again not winning.
"After two defeats, confidence had ebbed a bit but we showed real self-belief and I sound like a broken record but we have to find a way to win especially as we haven't delivered at home."
Gloucester wing Sharples celebrated his 200th competitive appearance for the club by scoring a try in an impressive performance.
Humphreys said: "Charlie is absolutely devastated that we didn't win but to play 200 games when he's only 27 is an incredible achievement, as such loyalty is rarely shown in the modern-day environment.
"He's the sort of player that the club needs to build itself around."
Source: PA
