England prop Mako Vunipola and winger Jack Nowell will miss the first two matches of Rugby World Cup in Japan, head coach Eddie Jones has said.
Vunipola, 28, suffered a recurrence of a hamstring injury during his international comeback in England's 57-15 win over Ireland last month and will not be fit enough to feature in either of England's opening World Cup games against Tonga and the USA.
"Mako definitely won't be but we feel he might possibly be right for game three or game four in the pool stage," Jones said. "He is a very important player and we are very confident that he will make a very important contribution for us."
Vunipola was sidelined for three months with a hamstring injury prior to the Ireland match, having required surgery when first picked up the injury in Saracens' Champions Cup final win over Leinster in May.
Teammate Jack Nowell is still recovering from an ankle injury that he sustained during Exeter Chiefs' 37-34 defeat to Saracens in the Gallagher Premiership Final in June that required surgery.
"Jack Nowell has taken the last couple of days off so we've had to hold him back a bit. He should be right, again similar to Mako. Everyone else is in full training."
England finished their World Cup preparations with a healthy 37-0 victory over Italy at Newcastle United's St James' Park ground on Friday.
England begin their World Cup campaign against Pool C opponents Tonga on Sept. 22.