Jamie Carragher believes Anthony Martial must be an extremely talented player given what he cost Manchester United.

The Red Devils paid £36million for the 19-year-old French forward, who joined from AS Monaco on deadline day, and his arrival has created a frenzy of reactions from all corners.

Former Liverpool defender Carragher is one who is treating the signing speculatively but acknowledges that the hefty fee the youngster has commanded indicates he has a very bright future.

"He's the most expensive teenager in world football, so it's a big price," he told Goal.com.

"He comes with a lot of potential, which is expected at that age, just getting to the French squad as well.

"With Monaco going out of the Champions League [in the play-offs] as well, it made it easier for Manchester United to get him.

"But it's certainly a position they needed to strengthen, striker-wise, with the players that have moved on.

"He's a young player and when you talk about potential you're still not quite sure but for that price, he must be some player."