“The small complaint is expected to keep Mount out until the international break next month,” United said in a statement.
The next international break takes place from Sept. 4-12.
United will host Forest at Old Trafford on Saturday before travelling to last season’s runners-up, Arsenal, on Sept. 3.
Erik Ten Hag’s side have made a stuttering start to the season, with their loss at Tottenham on Saturday following a controversial win over Wolves on the opening weekend.
Information from Reuters was used in this report.