To many observers, the Manchester United left-back situation was one that could have been anticipated and should have been addressed in the summer.

The fact United spoke to Manchester City about Algeria international Rayan Ait-Nouri on deadline day suggests they did view it as a potential issue.

After starting all 38 Premier League games last term and the first three this, Luke Shaw has played only twice since, and the number of games missed could reach double figures before the 31-year-old returns.

When Diogo Dalot lined up at left-back against Leeds, he became the fifth different player to start there for United in six games.

Aside from Shaw, none of the quintet could be regarded as a natural left-back.

However, after it was suggested Lisandro Martinez's post-match outburst following the defeat by Atletico Madrid was partly down to 20-year-old Ayden Heaven playing at left-back, sources did point out the youngster played more often in that role than in the centre during his youth days at Arsenal.

It was also suggested in the summer that United's coaching team did not believe 19-year-old Harry Amass, who was Shaw's stand-in during pre-season, was yet at the right level.

Amass' single appearance so far this season, as a substitute for the final 18 minutes against Sabah, backs up that view, although Michael Carrick has countered it.

"He's right in contention," Carrick said.

"At some point, young players need an opportunity. It's just finding the right time.

"Sometimes it's because there's an unfortunate thing happened to somebody else. Sometimes it's just you're doing so well we have to give you a chance.

"All the young players are in a similar boat. There's maybe four, five, or six of them trying to make that next step in terms of getting into the team and trying to start games, and Harry's definitely one of them."