Antonio Valencia
Antonio Valencia suffered a foot injury during the Manchester derbyGetty

Manchester United have confirmed that Antonio Valencia has had surgery on his injured foot that will keep him out of action for a considerable period of time. He sustained the injury in October in the derby at Old Trafford and has not featured in any game since.

United posted an update on Twitter confirming the news after Valencia had tweeted a picture of himself on the hospital bed. This will push the Red Devils' full-back situation into a further crisis, with Luke Shaw unavailable for a major part of the season with a broken foot. "#mufc can confirm @Anto_V25 has had an operation on his foot," said Manchester United's official Twitter account.

The winger, who has been deployed as full-back, was substituted in the 81st minute but no timeline given on the extent of his injury. However, the latest revelation means that he may be out for more than what was anticipated after the game. Van Gaal had initially revealed after the Manchester City game that his injury was sustained in the first half, but he let him continue while keeping Matteo Darmian warming up on the sidelines.

"He had a kick on his foot in the first half and then I let Darmian warm up on the touchline. But then he played further. However, at the end, he could not continue," Van Gaal had said after the game.

The news of his injury came after the Ecuadorian was excused from the national squad for the international break scheduled in November, but more information will be available when Van Gaal takes his next press conference when the league resumes. The Red Devils have been extremely unfortunate in the injury department when it comes to defenders, with Marcos Rojo and Phil Jones also spending time on the treatment table owing to multiple problems.

However, this has not affected their defensive solidity, having conceded only eight goals thus far, the best record in the league. Valencia played an important role in stunting current leaders City, keeping the game to a goalless draw and not allowing the leaders to open the gap on them.