Belgium manager Roberto Martinez has made note of how Romelu Lukaku has significantly matured since joining Manchester United.

The Belgian arrived at the club for a £75m fee and made a storming start to life at Old Trafford, netting ten goals in his opening nine games.

He then encountered a frustrating dry patch through October and November but has since recovered to take his tally to 21 goals by mid-february.

And Martinez, speaking to the BBC, was quick to point out that Lukaku was growing as an individual at Man United.

“When you play for the biggest clubs in the world, you have to accept criticism as well as praise and just get on with things,” he said.

“Rom has always done that. He is an incredible goalscorer and he is still very young. This has been a really important chapter in his career.

“He started his new chapter with United with flying colours and made almost a record-breaking start there but, from that point onwards, you just knew that expectations were going to be sky-high.

“At United, a striker almost has to score in every game and be part of a winning team every week, and that is something Rom had to embrace.

“This season, it has felt like every call-up we have had, he has been more mature and keen to learn from the situation he is in now.

“I have seen a huge increase in the level of his maturity, which will help him enormously. He wants to take on the responsibility of being the United player who carries the most expectation of helping the team get a positive result.”

There is a clear sense of cold determination and ruthless discipline to the way Lukaku goes about his game. Throughout his career he has always stressed that he continues to place emphasis on learning, on developing a wider understanding of the game.

And such an ethic has shone through in recent displays against Burnley, Newcastle United and Huddersfield town, where his manipulation of the ball stood out.

But that one burning question still remains: can he do it against the big sides? So far, the Belgian has gone missing in big games and you almost get the impression that he personally doesn’t have the same belief – that unique thrust about his demeanour – when pitted against the very best.

Whether this is down to defenders figuring out his game or a kind of psychological block is a matter of debate, but Lukaku, either way, will know what he needs to work on in the coming months and years.