Manchester United head coach Erik ten Hag has revealed that Anthony Martial is "improving" but remains on the sidelines with a troublesome back problem.

The 26-year-old has only made four appearances for the Red Devils this season, having struggled with a number of fitness problems since Ten Hag's arrival as head coach.

Martial missed the start of the campaign with a hamstring problem before returning against Liverpool, providing an assist in the second half of the 2-1 win over the Reds.

The France international was then missing due to an Achilles injury, which kept him out for five matches, before returning as a substitute in the Manchester derby.

Martial scored twice off the bench in his side's 6-3 loss to Manchester City before netting again as a substitute against Omonia in the Europa League on October 6.

© Reuters

The forward was handed a start against Everton on October 9 and set up Antony for his side's first of the match, but he only lasted 29 minutes due to a back problem.

The former Monaco youngster has now been missing for the team's last three Premier League games against Newcastle United, Tottenham Hotspur and Chelsea, in addition to the home European clash with Omonia.

There was hope that Martial could be back for Thursday's game with Sheriff Tiraspol, but Ten Hag has confirmed that the attacker remains unavailable for selection.

"He's improving. He's back on the [training] pitch, not in the group so we have to wait for that step. But hopefully he's back [soon]," Ten Hag told MUTV.

An impressive pre-season meant that Martial was expected to start the campaign as the team's first-choice centre-forward, but Marcus Rashford has instead largely operated through the middle this term.

© Reuters

Martial made the move to Man United from Monaco in September 2015, and he has now represented the club on 273 occasions in all competitions, contributing 82 goals and 52 assists in the process.

The Frenchman will soon enter the final 18 months of his contract at Old Trafford, but the Red Devils are believed to be keen to open discussions over a new long-term deal.

While Martial will again be out against Sheriff, Man United's attack will be boosted by the return of Cristiano Ronaldo.

Ten Hag confirmed during Wednesday's press conference that the 37-year-old would be back in the squad, having served his punishment for refusing to enter as a second-half substitute against Tottenham Hotspur last week.

Ronaldo has started all four of the team's Europa League matches this season and scored against Sheriff from the penalty spot in the reverse fixture in the middle of September.