Sam Burgess will make his England debut at centre when Stuart Lancaster's side host France on Saturday.
The former Great Britain rugby league player is one of three debutants, with centre Henry Slade and flanker Calum Clark the other new faces in the XV.
Head coach Lancaster says Saturday's match is the final chance for some of his players to impress before he selects his 31-man World Cup squad.
"The following week we'll probably change a lot," he said.
Burgess, 26, started his union career in midfield for Bath before switching to the back row.
Former England scrum-half Matt Dawson has questioned Burgess's "game-management" at inside centre, but Lancaster described the former South Sydney player, who switched codes last October, as a ball carrier who could threaten the gain line.
"It's an option for us to look at and it'll be an interesting insight to see whether it goes well at the weekend or not," he said.
"It's about what's right for the team. We'll see if he can translate what he does in training and see how it goes."
In addition to the three new players, full-back Alex Goode, prop Kieran Brookes and second row George Kruis start, with the men understood to be their rivals for places in the final squad - Danny Cipriani, Dave Attwood and Alex Corbisiero - on the bench.
Uncapped hooker Luke Cowan-Dickie is also among the replacements, while Owen Farrell and Richard Wigglesworth form an experienced half-back partnership.
|England's World Cup pool games|
|Friday, 18 September, 20:00 BST: England v Fiji, Twickenham Stadium|
|Saturday, 26 September, 20:00: England v Wales, Twickenham Stadium|
|Saturday, 3 October, 20:00: England v Australia, Twickenham Stadium|
|Saturday, 10 October, 20:00: England v Uruguay, City of Manchester Stadium|
'Players need to perform'
With centres Brad Barritt and Jonathan Joseph almost guaranteed places in the final squad, Burgess, Slade, Billy Twelvetrees and Luther Burrell are competing for the other centre spots.
Replacement Twelvetrees is set to be introduced early in the second half on Saturday.
"The three centres have a very good opportunity to put a marker down," said Lancaster.
"This isn't a team that's going to play Fiji," he said, referring to England's World Cup opener on 18 September. "This is a team to look at options for us."
Wood set to lead from the front
England will be led by Tom Wood, who was a contender for the captaincy when Lancaster first took over, before Chris Robshaw got the nod.
"I'm ecstatic to pull on an England shirt and that's all that really matters to me," said Wood.
"I'm more than happy to deputise for Chris and support him, he's done a great job. I'll lead the way this week but I know I am keeping it warm for Chris, he's still the man for the job."
'Morgan has opportunity to make a mark'
Ben Morgan, who broke his left leg in January, returned to full training on Friday and will start at number eight against France.
"I'm 100% confident he's ready to play the game," added Lancaster of the 27-cap Morgan, who was in good form for his country before injury.
"But obviously it's going to be a big step for him.
"He's got an opportunity to put his marker down but, equally, we've got other back-row options to consider as well. He's training well, he's confident and, as a consequence, we need to have a look at him."
|England team to face France|
|England: Alex Goode; Anthony Watson, Henry Slade, Sam Burgess, Jonny May; Owen Farrell, Richard Wigglesworth; Mako Vunipola, Rob Webber, Kieran Brookes, George Kruis, Geoff Parling, Tom Wood, Calum Clark, Ben Morgan|
|Replacements: Luke Cowan-Dickie, Alex Corbisiero, David Wilson, Dave Attwood, James Haskell, Danny Care, Danny Cipriani, Billy Twelvetrees|