The Dutch striker suffered the problem during last weekend’s 2-1 defeat at Swansea City and left the Liberty Stadium with his foot in a protective cast.
Speaking to the media before this weekend’s clash with the Black Cats at Old Trafford, Van Gaal revealed that the forward is the Red Devils’ only new injury concern.
“He [Robin] is the only injured player,” Van Gaal told MUTV. “He has an ankle injury. We have to wait and see how long that shall take.”
The Manchester United boss is hopeful that the injury will only keep Van Persie out of action for a maximum of a couple of weeks.
“It’s not heavy but it’s not one or two weeks,” he added.
Van Persie has been a regular fixture in Van Gaal’s United team this season. The 31-year-old has scored 10 goals and made two assists in 24 Premier League games for United this term.
Van Gaal also revealed that midfielder Michael Carrick is edging closer to a comeback from injury after he returned to training on Thursday.
“He [Michael] is very experienced and he can play in a very important position,” he continued. “But he also needs match rhythm. He trained only one time with us, with the group, so he needs to also play in the second team.”
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