England will be without captain Dylan Hartley on their tour of South Africa this June as he continues his recovery from concussion.
Hartley has not played since England's Six Nations defeat to Ireland last month and following specialist medical advice, has decided to take an extended period of rest over the summer.
It means the Northampton Saints hooker, 32, will play no part in the rest of the Aviva Premiership season or his country's three-Test series against the Springboks.
"I'm very disappointed that I will not be available for selection for Saints' remaining Premiership games, as well England's tour to South Africa," Hartley said.
"It has been recommended by specialists that I take a break this summer and while I find that decision hard to accept, it's important I listen to that advice.
"I intend to use this time to recover fully from my injury, so I can be ready to hit the ground running when pre-season training starts later this summer."
Hartley's absence in South Africa means Eddie Jones will have to select another player to lead his side, with Chris Robshaw, Owen Farrell, George Ford and Maro Itoje all in contention pending selection.