Elliot Daly has been omitted from England's 32-man training squad for Sunday's clash with the Barbarians but Piers Francis is back having recovered from coronavirus.
No reason has been given by the Rugby Football Union for Daly's absence, with head coach Eddie Jones set to give an update on the Saracens centre at lunchtime on Tuesday.
However, he is unfit to train this week and will play no part in the curtain-raiser to England's autumn schedule.
Francis was picked in Jones' first squad since the Six Nations earlier this month but was forced to withdraw and self-isolate after testing positive for Covid-19 as a result of playing Sale on September 29.
Tom De Glanville's hopes of making his England debut in the non-cap international at Twickenham have been dashed following his omission from the 32 who will gather at their training base in south west London.
"This is an important game for us and we're looking forward to getting back to Twickenham and playing rugby," Jones said.
"We've had two really good camps, going back to basics and how we want to play. The Barbarians squad has a rich blend of talent, so this week we'll be testing ourselves under pressure and looking to take our game to the next level."
England training squad:
Backs: A Crossdale (Saracens), F Dingwall (Northampton Saints), O Farrell (Saracens), G Ford (Leicester Tigers), P Francis (Northampton Saints), G Furbank (Northampton Saints), W Heinz (Gloucester Rugby), J Joseph (Bath Rugby), O Lawrence (Worcester Warriors), J Marchant (Harlequins), J May (Gloucester Rugby), A Mitchell (Northampton Saints), O Thorley (Gloucester Rugby), A Watson (Bath Rugby), B Youngs (Leicester Tigers).
Forwards: T Curry (Sale Sharks), A Dombrandt (Harlequins), T Dunn (Bath Rugby), C Ewels (Bath Rugby), E Genge (Leicester Tigers), J George (Saracens), J Heyes (Leicester Tigers), T Hill (Worcester Warriors), M Itoje (Saracens), A Moon (Northampton Saints), B Obano (Bath Rugby), D Ribbans (Northampton Saints), W Stuart (Bath Rugby), S Underhill (Bath Rugby), B Vunipola (Saracens), M Vunipola (Saracens), M Wilson (Newcastle Falcons).