Mako Vunipola is unlikely to play much part in England's Rugby World Cup warm-up matches after Saracens confirmed the prop will require "a minimum of three months to recover" from hamstring surgery.
The 28-year-old, who has appeared for England 53 times, came off in the first half of Sarries' 20-10 European Champions Cup final victory over Leinster in Newcastle last weekend.
Speaking on Thursday, Saracens' director of rugby Mark McCall had said Vunipola's domestic season was likely over, meaning he would play no further part in the defending Premiership champions' bid to regain the trophy.
McCall had said Vunipola would not miss the World Cup but, with the club now confirming he will be absent until at least mid-August, there is little time for him to get up to speed before Eddie Jones' side travel to Japan for the tournament.
Vunipola appears set to miss both warm-up contests against Wales in August, while the clash with Ireland on August 24 and Italy on September 6 may also come too soon.
England then head to the World Cup, with their first fixture against Tonga on September 22.