England have suffered a setback on the eve of their Autumn Nations Cup final against France after Mako Vunipola was ruled out by an Achilles problem.
Prop Vunipola sustained the injury in the win over Wales last Saturday and has been unable to recover in time for Sunday's Twickenham showdown.
Ellis Genge is promoted from the bench into the starting XV, with Joe Marler filling the vacancy among the replacements.
"Mako picked up an injury in last week's game," England attack coach Simon Amor said. "We've given him every opportunity to recover for this one but unfortunately he hasn't made it."
Vunipola had re-established himself as England's first-choice loosehead after Marler missed the start of the autumn due to a knee injury, with Genge now second in the revised pecking order for a position where Eddie Jones' side have genuine depth.
"It's disappointing to lose any player," Amor said. "In Ellis Genge and Joe Marler we've got two outstanding loose-heads there.
"They've trained well this week. Ellis is a real bowling ball in terms of his carries, so he'll bring that aggression with the ball.
"He's a very destructive scrummager and he brings a real energy to the team. He's a great one to bring in."
England hooker Jamie George echoed Armor's words about the energy Genge will bring, and said the 25-year-old fully deserves the opportunity to start.
"It's doesn't make too much of a change for us," George said.
"It's obviously a big loss missing a player of Mako's calibre; I think he's playing some of the best rugby of his career at the moment.
"But at the same time what an exciting prospect to have Ellis step in. We'll certainly not lose much in terms of the energy levels!
"I think Ellis really deserves his chance because I think he's really stepped up this autumn campaign."