England scrum-half Alex Mitchell will miss the Six Nations match against Scotland on Saturday after suffering a knee injury.
The 26-year-old will likely be replaced by Danny Care or Ben Spencer for the Calcutta Cup clash at Murrayfield.
Bristol scrum-half Harry Randall has been called into Steve Borthwick’s 36-man training squad as cover.
An England spokesperson said Mitchell’s injury requires “further investigation” to determine its severity.
Mitchell has started in both of England’s victories against Italy and Wales so far in the Six Nations.
The Northampton Saints scrum-half has established himself as first choice for England since breaking into the squad for last autumn’s World Cup.
England are second in the Six Nations standings with eight points, behind defending champions Ireland.
There is full commentary of Scotland against England next Saturday on BBC 5 Live, kicking off at 4.45pm, with all the latest news available on the Rugby Union Daily podcast on BBC Sounds.
England squad to face Scotland
Forwards: Ollie Chessum (Leicester Tigers), Dan Cole (Leicester Tigers), Alex Coles (Northampton Saints), Luke Cowan-Dickie (Sale Sharks), Chandler Cunningham-South (Harlequins), Ben Curry (Sale Sharks), Theo Dan (Saracens), Alex Dombrandt (Harlequins), Ben Earl (Saracens), Charlie Ewels (Bath Rugby), Ellis Genge (Bristol Bears), Jamie George (Saracens), Joe Heyes (Leicester Tigers), Maro Itoje (Saracens), Joe Marler (Harlequins), George Martin (Leicester Tigers), Beno Obano (Bath Rugby), Ethan Roots (Exeter Chiefs), Will Stuart (Bath Rugby), Sam Underhill (Bath Rugby)
Backs: Danny Care (Harlequins), Elliot Daly (Saracens), Fraser Dingwall (Northampton Saints), Immanuel Feyi-Waboso (Exeter Chiefs), George Ford (Sale Sharks), Tommy Freeman (Northampton Saints), George Furbank (Northampton Saints), Ollie Lawrence (Bath Rugby), Max Ojomoh (Bath Rugby), Harry Randall (Bristol Bears), Tom Roebuck (Sale Sharks), Henry Slade (Exeter Chiefs), Fin Smith (Northampton Saints), Ben Spencer (Bath Rugby), Freddie Steward (Leicester Tigers), Manu Tuilagi (Sale Sharks)