Sam Simmonds will miss England's tour of Australia in July as he needs surgery on a hip injury.
Exeter's 27-year-old, who broke the Premiership single-season try-scoring record last year, played in all five of England's Six Nations games this year.
He has not played since the Chiefs' Heineken Champions Cup last-16 first-leg win over Munster on 9 April.
"It's been a niggly hip injury that's been causing him pain," Exeter director of rugby Rob Baxter said.
"The restrictive thing has been the pain, not so much the function.
"If he gets this sorted now that means he can have a good recovery time and a good pre-season, and it's a huge year for anybody who's got international ambitions next year, it being a World Cup year.
"So in some ways it'll really help him get himself to the level he was a couple of years ago when he was banging tries in from everywhere.
"He'll want to follow that through because that's what led to his international and Lions recognition."
He joins fellow England players Luke Cowan-Dickie, Jonny Hill and Jack Nowell on the Exeter sidelines.
Hill has been out since January with a stress fracture, Cowan-Dickie has not played since limping off against Wales with a knee ligament injury in February while Nowell broke his arm against France three weeks later.
Exeter have no players in the England squad to face the Barbarians next month with centre Henry Slade rested, but Baxter believes Hill, Cowan-Dickie and Nowell could be fit for England's tour to Australia.
"They'll be in with England for some rehab and so England can have a look at them early next week," he said.
"They're progressing pretty well at the moment, and if that progression continues there's no reason why not.
"The tour is still a little way away. The last round of the Premiership isn't for another couple of weeks, then you've got a semi-final and a final before the tour heads off.
"It's still over a month away, so they've still got a decent amount of rehab time before those decisions need to be made."
England tour of Australia
Saturday 2 July - Optus Stadium, Perth. Kick-off: 10:55 BST
Saturday 9 July - Suncorp Stadium, Brisbane. Kick-off: 10:55
Saturday 16 July - Sydney Cricket Ground, Sydney. Kick-off: 10:55
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