Stuart Lancaster has defended his decision to select Owen Farrell and Sam Burgess for England's World Cup game against Wales on Saturday.

Despite playing just 112 minutes of Test rugby, Burgess has replaced the injured Jonathan Joseph at inside-centre, while Farrell comes in for George Ford, who started at fly-half for last Friday's 35-11 victory over Fiji.

Criticism of the latter change was directed at Lancaster as soon as news of the team surfaced, but he insists that it was not a risk to recall Farrell.

"I don't think putting an in-form and confident Owen Farrell into the team is a risk," the England coach told reporters.

Lancaster was also eager to give his backing to Burgess, who has won just three caps since switching codes, as he prepares for the biggest game of his short union career.

"People said it was a gamble to put Sam into the 31-man squad. Day by day, week by week he has proven people wrong," he added in his pre-match press conference.

"It's a big game for Sam but I think he's more than proven over the last three months he's capable of playing at this level."

Billy Vunipola has also been recalled in place of Ben Morgan, who will miss the game with a knee injury.