Manchester United manager Jose Mourinho has confirmed that Marouane Fellaini has undergone a successful operation on his knee injury.

Fellaini came off the bench during United's 2-0 defeat to Tottenham Hotspur in midweek but lasted less than eight minutes before being forced off with a knee ligament problem.

The Belgian has now undergone surgery to treat the injury and is expected to be sidelined until March, ensuring that his World Cup hopes remain alive this summer.

"He had surgery this morning. It is not the end of the season, not at all," Mourinho told reporters at his post-match press conference.

"It is a small intervention in his external meniscus and I want to believe by the end of March he can be back."

Fellaini has made just 16 appearances for United across all competitions this season, scoring four goals.