Manchester United midfielder Michael Carrick will miss up to the first three months of manager Louis van Gaal's reign with an ankle injury.

Van Gaal mentioned at his unveiling press conference that Carrick had suffered an injury and would be out for "a long time, too long".

And the club later confirmed on Twitter: "Michael Carrick has had surgery this morning on his left ankle ligaments and will be out for 10-12 weeks."