England suffered a fresh setback to their Six Nations title defence when Sam Underhill became the latest player to withdraw from Eddie Jones' squad because of injury on Tuesday.
The Bath flanker pulled out with a hip problem that could sideline him from the whole tournament.
Underhill, who was in line to start England's competition opener against Scotland at Twickenham on 6 February, has been replaced in the squad by Jack Willis.
"It's disappointing for him but the outlook is pretty positive," said Bath director of rugby Stuart Hooper, who added he expected Underhill to be fit before the end of the Championship.
"We're talking weeks more than anything else.
"He (Underhill) picked it up against Wasps earlier this month and it probably has been bit of a niggle for him. He was assessed this (Tuesday) morning by the England medics and the decision was made.
"He's been in great form and has delivered some top performances. We know the destructive nature of Sam's game and the ability he's got on both sides of the ball now, with carrying and defence.
"This injury is a setback but he'll come back to us and get the very best treatment."
Tuesday's announcement came just a day after veteran prop Joe Marler withdrew from the set-up to spend more time with his family during the coronavirus pandemic and lock Joe Launchbury was ruled out of at least the first three rounds with a broken leg.
Marler's decision left Ellis Genge as the only capped loosehead prop still in the squad after Mako Vunipola was omitted because of an Achilles injury.
Turnover specialist Willis, who made his Test debut during the Autumn Nations Cup in November, has been promoted from England's 12-strong 'shadow squad' and will compete with Mark Wilson and Ben Earl for the vacancy created by Underhill's absence.