However, Shaw revealed that Ibrahimovic was up and walking in the dressing room and is hopeful that the injury is not too serious.
"I knew it did not look so good on television, but he seems to be in good spirits," the left-back told Sportbladet.
"He walked around in the dressing room. I do not know the extent of his injury, of course, but I saw him in there and he was optimistic. Hopefully it is not too bad for him. We hope it is not too serious and he seems okay."
Ibrahimovic has scored 28 goals across all competitions for United this season, but is unlikely to feature in Sunday's Premier League clash with Burnley.