Manu Tuilagi and Luke Cowan-Dickie are both missing from England’s training group for this week’s three-day camp in Bristol, while Jonny Hill is also out.
Tuilagi is recovering from a hamstring strain, while Cowan-Dickie awaits word on the severity of a knee injury sustained in Saturday’s 23-19 Guinness Six Nations victory over Wales.
As Tom Curry recovers from the concussion he suffered in Round 3 at Twickenham, Gloucester’s Lewis Ludlow has been called up as back-row cover.
Hill, like Tuilagi, has been unable to play in the Six Nations due to a high ankle stress fracture, but the Exeter lock will continue his rehabilitation with England.
Will Goodrick-Clarke, an uncapped London Irish prop, has been included, but Elliot Daly and George Ford have been left out of the 25-man team that will begin preparations for the match against Ireland on March 12.