London - Gloucester centre Billy Twelvetrees and flyhalf Freddie Burns were added to England's squad for their upcoming international programme on Sunday.
Twelvetrees has been brought in as temporary cover for London Irish's Jonathan Joseph, carrying an ankle injury, while Burns replaces Harlequins centre Jordan Turner-Hall, who has an inflamed knee.
"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," said England coach Stuart Lancaster.
"JJ is continuing his recovery from an ankle injury and this is a good chance to get Billy in for training."
In all 36 players were set to join up at England's Pennyhil Park base in Bagshot, south-west of London, on Sunday including Courtney Laws and Dylan Hartley, who will have their respective knee injuries assessed by Lancaster's medical staff.
"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," Lancaster added.
"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.
The Fiji match is the first of four Tests on successive weekends at Twickenham which will also see England's at home to southern hemisphere giants Australia, South Africa and world champions New Zealand.
This year's autumn matches in Europe have added significance as the teams in the top four of the International Rugby Board rankings at the end of the series will be seeded for next month's draw for the 2015 World Cup in England.
Revised 36-man England squad for the Twickenham Tests against Fiji (November 10), Australia (November 17), South Africa (November 24) and New Zealand (December 1):
Backs (16): Anthony Allen (Leicester), Chris Ashton (Saracens), Brad Barritt (Saracens), Mike Brown (Harlequins), Freddie Burns (Gloucester), Danny Care (Harlequins), Lee Dickson (Northampton), Owen Farrell (Saracens), Toby Flood (Leicester), Alex Goode (Saracens), Jonathan Joseph (London Irish), Ugo Monye (Harlequins), Charlie Sharples (Gloucester), Manu Tuilagi (Leicester), Billy Twelvetrees (Gloucester), Ben Youngs (Leicester)
Forwards (20): Mouritz Botha (Saracens), Dan Cole (Leicester), Alex Corbisiero (London Irish), James Haskell (Wasps), Phil Dowson (Northampton), Dylan Hartley (Northampton), Tom Johnson (Exeter), Courtney Lawes (Northampton), Joe Marler (Harlequins), Ben Morgan (Gloucester), Tom Palmer (Wasps), Geoff Parling (Leicester), David Paice (London Irish), Chris Robshaw (Harlequins, captain), George Robson (Harlequins), Mako Vunipola (Saracens), Thomas Waldrom (Leicester), David Wilson (Bath), Tom Wood (Northampton), Tom Youngs (Leicester)