Radamel Falcao has insisted that his knee trouble is behind him as he prepares to begin life at Manchester United.

The Colombian striker missed the World Cup this summer because of a serious injury, but has stressed that he has no concerns over his improving fitness.

He told reporters at his official unveiling: "I started to play two months ago with Monaco, I improved in the last couple of months, I have scored goals and I am confident with my physical form and I am comfortable with my knee."

Falcao has joined United on a season-long loan from AS Monaco for a reported fee of £6m, and could make his debut against Queens Park Rangers in the Premier League on Sunday afternoon.