England will be without first-choice scrum-half Alex Mitchell for Sunday's Nations Championship opener against Australia, and head coach Steve Borthwick has summoned Bristol's Harry Randall and Bath's Ben Spencer to cover the gap.
Mitchell hurt a hamstring during Northampton's Prem victory over Gloucester on Saturday. A scan on Tuesday is expected to reveal how serious the damage is.
His Northampton teammate Archie McParland is also unavailable. The uncapped scrum-half, on just his second senior call-up, strained a calf while training with England last week.
That leaves Leicester's Jack van Poortvliet in line to start at No 9, with one of the two newcomers on the bench. Mitchell's place is secure once he is fit, but with the World Cup less than a year off, this week gives Randall and Spencer a valuable opening.
The pair offer different tools. Randall is known at Bristol for darting runs around the breakdown, while Spencer, only recently back playing for Bath after shoulder surgery, has a reputation for precise tactical kicking, and the coaches are weighing how the switch could alter the game plan.
Changes across the squad
Several backs with recent fitness doubts made the 36-player group, including Gloucester's Seb Atkinson, Exeter's Immanuel Feyi-Waboso and Northampton's Fin Smith. Bath's Max Ojomoh and Saracens' Noah Caluori were cut from last week's selection.
Harlequins fly-half Marcus Smith, in strong form, is widely tipped to challenge Fin Smith for the No 10 shirt. His clubmate George Furbank is pressing hard for a start at full-back.
Up front, the only change sees 21-year-old Bath hooker Kepu Tuipulotu, another uncapped player, withdraw injured. Saracens' Theo Dan comes back in.
Players reported to the team's Pennyhill Park base on Monday night, taking advantage of a Prem break that runs until December.
The Australia match is England's round-four fixture. Japan and New Zealand follow in rounds five and six, ahead of the finals weekend at the end of November, and Borthwick said the series is England's last look at southern hemisphere teams before the World Cup.
These fixtures take on added significance this autumn as they represent our final opportunity to face southern hemisphere opposition before next year’s World Cup.
Steve Borthwick, England head coach
Scotland lose two forwards
Scotland are dealing with their own losses. Flanker Jamie Ritchie, facing four to six weeks out with a suspected medial collateral ligament injury from Glasgow's United Rugby Championship win over Lions last Friday, and prop Elliot Millar Mills, who hurt a knee in Newcastle's Prem defeat by Saracens on Saturday, will miss all four November matches.
Gregor Townsend has added three Edinburgh forwards: props Ollie Blyth-Lafferty and D'Arcy Rae and flanker Freddy Douglas. Scotland open against New Zealand on Saturday, then meet Australia and Japan, with every match at Murrayfield.
