It's been a very topsy-turvy debut campaign for Romelu Lukaku at Manchester United.

The Belgian forward scored 11 goals in his first 10 matches for the club in all competitions, including seven in as many Premier League outings.

That included a brace on his league debut against West Ham, as well as a goal against his former club Everton, having left Goodison Park for £90m in July after four seasons on Merseyside.

But since September turned to October, and in the months following, Lukaku has seemingly lost his golden touch, finding the net in the Premier League only three times in 13 games.

He went through similar spells at Everton, failing to score from March 2016 until September of that year, when he bagged a hat-trick in a 3-0 win at Sunderland, ending a run of 18 scoreless matches.

But having become (at the time) the fifth-most expensive player in the history of football, better has been expected of the 24-year-old at Old Trafford.

This is particularly because United 'play to win', not draw, which he claimed of his former club, but Lukaku has staggeringly failed to score against any team in the top eight of the Premier League.

In his defence, a lot has been expected of him, with Zlatan Ibrahimovic only recently returning from what looked a career-ending knee injury, while Jose Mourinho doesn't appear to like Marcus Rashford or Anthony Martial up front.

But Mourinho believes the lack of any real support up-front has been a burden to the Belgian, and has put his form down to tiredness.

Lukaku has started every single game in the league this term, and the Portuguese claimed he has been unable to rest his star man.

"The boy is tired. He's physically a monster, but not a machine, and he's feeling it," he started.

"The other day I said 19 matches in the Premier League, now I say 20 matches in the Premier League, playing 90 minutes, I think for a striker, any player, he's absolutely incredible.

"But if you are a central defender, a holding midfield player, where you can control your energy, positional play, you can resist and survive.

"But for a striker to play 20 matches in the Premier League, 90 minutes, I have to be grateful. Is he unlucky in our box in recent matches? He was in the picture. It was not a direct influence on just him, but he was in the picture in some of the last goals we conceded, but it's a consequence of a player that really needs a little rest.

"But the guy is fantastic for me and for the team and gives absolutely everything and I've no critics."

Lukaku will be hoping he can find his form at home to Southampton on Saturday before his first return to Everton two days later, where he can expect a hostile reaction.

The Belgian provoked the ire of Evertonians during his time at Goodison Park for comments he made on several international trips, where he stated he needed to leave the club to improve his career.

He was booed by the away supporters during United's 4-0 win against the Blues in September, which was met with the celebration above when he inevitably found the net.

If Lukaku can do the same on Monday night, expect a similar response from the Belgian.