Bristol prop Kyle Sinckler is set to miss England’s tour of Australia due to a back injury, the PA news agency understands.
Sinckler has not played since Bristol were eliminated from the Heineken Champions Cup by Sale in mid-April.
While his injury will not require surgery, it is thought the focus this summer will be on rest and rehabilitation before next season as Bristol continue managing his recovery.
The 29-year-old, who has won more than 50 caps, made his Test debut in 2016 and has proved a key figure during England head coach Eddie Jones’ reign.
He was not named by Jones in a 35-man England squad for a three-day training camp this week.
Jones has already lost Sale centre Manu Tuilagi (knee) and Exeter back-row forward Sam Simmonds (hip) from his Australia tour plans.
England tackle the Wallabies in Perth on July 2, then in Brisbane seven days later and finally Sydney on July 16.
And with the Premiership play-offs and final still to take place, Jones will be keeping his fingers crossed for no further setbacks.
Wings Jonny May and Jack Nowell, meanwhile, are included for the three-day gathering in Teddington.
May made his comeback for Gloucester on Saturday, featuring as a second-half substitute after five months out recovering from a knee injury.
Nowell, who broke his arm during England’s Six Nations defeat against France in March, also returned for Exeter during the final round of regular season Gallagher Premiership action.
There are first involvements in a senior England camp for Biyi Alo, Charlie Atkinson, Freddie Clarke, Sam Jeffries and Namibia-born Exeter prop Patrick Schickerling.
Players from Premiership semi-finalists Leicester, Saracens, Harlequins and Northampton were not considered for selection.
The list of uncapped players also includes Wasps back Paolo Odogwu and Bath centre Max Ojomoh.
Exeter hooker Luke Cowan-Dickie and Bath wing Anthony Watson will attend the camp to undertake rehab work as they continue to recover from injuries.
Jones said: “With a number of players unavailable because of the Premiership semi-finals, we’ve got the opportunity to call up some new players.
“It’s a great opportunity to learn about them and see what potential they have to play a part in the Australia tour.”
May missed this season’s entire Six Nations campaign, as did Exeter lock Jonny Hill, who is also included.
Hill has not played since early January due to a stress fracture of his lower leg.
Elsewhere, exciting London Irish back Henry Arundell earns another chance to impress as Jones runs the rule over players ahead of the trip Down Under.