Manchester United will have to make do without defender Diogo Dalot when Southampton visit Old Trafford in the Premier League on Thursday night.

Dalot was sent-off just past the hour mark during United's FA Cup third round triumph over Arsenal at the Emirates Stadium on Sunday afternoon. He was given a second yellow card for a reckless challenge on Gunners midfielder Mikel Merino.

Despite Arsenal capitalising on their numerical advantage instantly, drawing level through Gabriel just two minutes later, United produced a heroic defensive showing to take the contest to extra-time and then penalties. Ruben Amorim's side progressed on spot-kicks, of course, winning 5-3.

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As a result of Dalot being sent-off for two bookable offences, he must now serve a one-match suspension, meaning he will miss the upcoming clash with the Saints. Red card suspensions cover all domestic competitions, meaning he will have to serve the ban in United's next fixture rather than in the FA Cup fourth round.

The 25-year-old, who has operated as United's left wing-back in recent weeks, has been a virtually ever-present fixture under head coach Amorim, starting 12 of his first 13 games in charge. He has played every minute in the Premier League since his appointment.

With the United head coach gradually reducing the number of changes he has made to his starting XI in recent matches, Dalot's suspension means he will be forced into at least one against the Saints. United are not currently blessed in the left wing-back department, meaning Amorim does not have an awful lot of scope to replace his fellow countryman.

If the United boss goes down the route of making a like-for-like change, Tyrell Malacia is the obvious candidate to replace him. The former Feyenoord defender stepped off the bench ahead of the start of extra-time at the Emirates and contributed to United's sterling defensive effort.

Malacia, 25, has made five appearances since returning from a long-term injury lay-off in November, making four starts. He has been substituted on each of those four occasions, being taken off at half-time three times.

If Amorim is not of the opinion Malacia should take Dalot's place, his other option is to move Noussair Mazraoui to the left-sided wing-back role and bring Amad back into the team as the right wing-back. The latter started the clash with Arsenal on the bench after struggling with a "small issue" in midweek.

The Ivorian, who scored one of United's five successful penalties in the shootout victory over the Gunners, has played as the right-sided No.10 in recent weeks, meaning Mazraoui has been operating as the right-sided wing-back.

However, the Moroccan's versatility and experience of playing on the left means that he could be a realistic option to cover Dalot's absence. He played as a left-back under Erik ten Hag, as well as at left-sided centre-back in the Premier League defeat to Arsenal under Amorim last month, meaning he should be able to adapt to the left wing-back role.

If Mazraoui is elected to replace Dalot, meaning Amad comes back into the team at right wing-back, Alejandro Garnacho could start for the second game running, lining up as the right-sided No.10. He provided the assist for Bruno Fernandes' opener against Arsenal and delivered a spirited performance.