- Lukaku gets a nickname from his team-mates because of his training regime
- The Manchester United striker was injured in the 2-1 victory over Arsenal
- The 24-year-old is doubtful for the Premier League tie against Brighton
Manchester United striker has been nicknamed 'Rocky' by his team-mates because of his incredible training ethic.
The nickname is a nod to Sylvester Stallone's iconic boxing character in the cult Hollywood movie series.
The Belgium international attacker is battling to get fit for the rest the remaining games of the season at present after picking up an ankle injury against Arsenal.
The 24-year-old was forced off late as his Red Devils pals are cheering him up after bulking up in training.
An Old Trafford source said: "He has been absolutely smashing training and wants to be peak for the World Cup and Belgium.
"He's one of the first in for the warm-up on the bikes and is then hitting the gym for an hour after normal training has finished.
"They say he is more ripped than normal at present and knows he isn't going to have a full pre-season this summer.
"He is trying to kill two birds with one stone. Jose is obviously loving it, as it is setting a firm message out to the others.
"He is is full on 'Rocky' training mode and seems to be preparing more for 12 rounds of boxing than a game of football."
Lukaku is feared to have suffered a foot problem after being forced off against Arsenal and it will keep him out of United's clash against Brighton on Friday.
The six-foot-plus attacker is also facing a fitness battle to meet up the FA Cup final match next weekend against Chelsea at Wembley.
Lukaku started his journey with Chelsea in 2009 but he could not make an impact as he was loaned to West Brom after failing to score in 10 senior appearances.
However he banged in 17 goals in 35 matches at the Hawthorns and moved to Merseyside in the following season on loan.
At Everton, Lukaku continue his goal scoring exploits for the Toffees as he scored 15 goals in 31 appearances, which made his move permanent at Goodison Park.
In the next three seasons at Everton the Belgian scored 53 goals in 110 matches before making a big summer move move to United last summer.
He has currently scored 16 goals in 34 matches in all competitions and Lukaku has now developed into one the most feared center-forward in world football.
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