Harlequins scrum-half Karl Dickson will be out for up to 10 weeks after having surgery on a hand injury.
The 33-year-old sustained the injury in the 42-9 defeat by Montpellier in the European Challenge Cup last weekend.
"Thanks to Mike Hayton for fixing my finger. He did a great job. On to rehab now," the uncapped Englishman tweeted.
Dickson, who moved to the Twickenham Stoop from Bedford Blues in 2009, has scored one try in 11 appearances for Quins this season.
With first-choice scrum-half Danny Care in the England squad for the Six Nations, Tito Tebaldi will make his first Premiership start for Harlequins against Newcastle on Sunday.