Gloucester fly-half Freddie Burns and centre Billy Twelvetrees have been added to the England squad ahead of the QBE autumn international series.
Burns has been called up to replace Harlequins centre Jordan Turner-Hall, who is suffering from an inflamed knee.
Twelvetrees also linked up with the England squad at Pennyhill Park to provide temporary injury cover for Jonathan Joseph, the London Irish centre who is carrying an ankle injury.
A total of 36 players were scheduled to convene on Sunday night, including Dylan Hartley and Courtney Lawes who will have their respective knee injuries assessed by the England medics.
England play Fiji at Twickenham on Saturday and then face Australia, South Africa and New Zealand in a challenging autumn campaign.
England head coach Stuart Lancaster said: "Freddie has been playing well in the Aviva Premiership and, with Jordan needing to stay at Harlequins for treatment, we are keen to have a look at him.
"JJ is continuing his recovery from an ankle injury and this is a good chance to get Billy in for training.
"As last week, George Robson and David Paice come in as an injury replacements for Courtney Lawes and Dylan Hartley. Both will be assessed and treated in camp and it is important that they stay with the squad as much as possible.
"We had a productive week at St George's Park and got a lot of work done. Now we are back at Pennyhill we will sharpen our focus towards Fiji on Saturday."