Wasps lock Joe Launchbury and Saracens prop Mako Vunipola are in line to make their England debuts against Fiji at Twickenham on Sunday (Fiji Time) after being retained in a 23-man matchday squad on Tuesday.
Launchbury, who only joined the squad on Monday as injury cover for Tom Palmer was preferred by England coach Stuart Lancaster to Saracens second row Mouritz Botha and Harlequins' George Robson.
Lancaster is due to confirm his starting XV and eight-man bench -- teams are being allowed a maximum of eight replacements rather than seven this season as part of a law amendment trial -- on Thursday.
"We have had a good two days back at Pennyhill Park (England's training base in Bagshot, south-west of London) and the players have been very focused on delivering against Fiji," Lancaster said Tuesday.
"Saturday is a great opportunity for us to put a marker down and deliver a quality performance.
"It's great to have young players such as Mako Vunipola and Joe Launchbury get their opportunities in the match-day 23 and we are excited about the potential of the squad.
"We were keen to get Joe in, particularly in light of his recent form."
After Fiji, England host Australia, South Africa and New Zealand on consecutive weekends at Twickenham.
Lancaster's men need to at least hold onto the fourth place they currently occupy in the International Rugby Board rankings if they are to be seeded for the 2015 World Cup in England and so avoid the likes of New Zealand, the reigning champions, in next month's draw for the pool phase.
England 23-man squad to play Fiji
Backs (10): Brad Barritt (Saracens), Mike Brown (Harlequins), Danny Care (Harlequins), Owen Farrell (Saracens), Toby Flood (Leicester Tigers), Alex Goode (Saracens), Ugo Monye (Harlequins), Charlie Sharples (Gloucester), Manu Tuilagi (Leicester), Ben Youngs (Leicester)
Forwards (13): Dan Cole (Leicester), Tom Johnson (Exeter), Joe Launchbury (Wasps), Joe Marler (Harlequins), Tom Palmer (Wasps), David Paice (London Irish), Geoff Parling (Leicester), Chris Robshaw (Harlequins, capt), Mako Vunipola (Saracens), Thomas Waldrom (Leicester), David Wilson (Bath), Tom Wood (Northampton), Tom Youngs (Leicester)