Luke Shaw could miss the start of next season because of the foot injury he sustained in Manchester United’s 1-1 draw with Swansea City on Sunday.

A scan undertaken by the left-back on Tuesday morning revealed serious ligament damage, with it being understood Shaw fears he may not be able to recover until after the start of the 2017-18 campaign.

Shaw was forced off after nine minutes at Old Trafford and appeared in some pain. After the match United’s manager, José Mourinho, said: “Luke Shaw’s must be a big injury because to leave the pitch after 10 minutes I am expecting a very big injury.”

The injury is a severe blow to Shaw. It is his second serious problem in two years after the double leg break he suffered during a 2-1 Champions League loss at PSV Eindhoven in September 2015.

Shaw did not recover from that setback until this season and had endured a difficult first season under Mourinho. The Portuguese has often criticised the 21-year-old, the first time coming after a 3-1 defeat at Watford in September. He has also implored Shaw to ensure the “football brain and professional brain” match his talent, and has dropped him completely from match-day squads on several occasions.

This caused Shaw to consider his future at the club, although publicly he vowed to prove Mourinho wrong and had fought his way back into contention.

Shaw’s absence means Mourinho will be without eight injured players for Thursday’s Europa League semi-final first leg at Celta Vigo.