Reuters - Scoring against arch-rivals Liverpool on his debut last weekend was the perfect way for Anthony Martial to introduce himself to his team-mates and Manchester United's supporters, midfielder Michael Carrick has said.

Martial became the world's most expensive teenager when United signed him from Monaco for a reported £36 million pounds (S$78 million) on transfer deadline day, and although he is well known in France, the size of his fee and relatively low profile due to his age prompted murmurs of surprise in England.

Midfielder Carrick joined captain Wayne Rooney in admitting that he did not know much about the teenager when United signed him, but backed Martial to have a bright future at United, based on his debut performance.

"I have to be totally honest, I didn't know an awful lot about him but I do now! To start like that, you can't really ask for more," Carrick was quoted as saying by the club's website.

Martial put the gloss on United's 3-1 win at the weekend after coming on as a second-half substitute when he danced past three defenders in the 86th minute and side-footed the ball home.

"It doesn't get any better than that, does it? Coming in and coming on, scoring against Liverpool like that," the 34-year-old Carrick added.

"He has done well to get in that position and I thought the finish was terrific, how he just slotted it home, he was so calm and composed. You can't ask for a better start.

"He has announced himself and everyone has seen it on the big stage. It's a good start for him. I am sure his confidence will be sky-high after that.

"It's a good way to settle him and if that has raised expectations then so be it, but that is part of the game."