Manchester United boss Ole Gunnar Solskjaer has backed Jadon Sancho to come good after a slow start with the club.

The 21-year-old has made five appearances for Untied since signing from Borussia Dortmund for around £73million after a high-profile transfer pursuit that lasted over a year.

England international Sancho arrived to huge fanfare, though he is yet to register a goal or assist going into Sunday's Premier League trip to West Ham.

A frustrating start for Sancho continued when he was sacrificed in the first half of Tuesday's Champions League loss to Young Boys, the winger taken off as part of a reshuffle when Aaron Wan-Bissaka was sent off.

Solskjaer, though, insists nothing has changed in his evaluation of Sancho, who he feels can be a "top forward" for United over more than a decade.

"He is learning all the time," Solskjaer told reporters before the West Ham clash.

"As I said in training as well, he is learning our methods, he is learning the Premier League and of course, he knows the Champions League already from being at Dortmund.

"He is a young boy, he is only 21 and he will improve. 

"We signed him as we see a top forward for 10, 12, 15 years and I have not changed my mind on that.

"He is so clean on the ball and is enthusiastic to learn and that is such a big thing when you come to Manchester United.

"You are always going to get a chance and you play with some of the best players in the world, you are getting some fantastic coaching with the coaches I have got too."

United will do battle with their former manager David Moyes when they take on West Ham, with Sancho not a certainty to start given Paul Pogba, Bruno Fernandes, Mason Greenwood and Cristiano Ronaldo are among the options in attacking positions.

Since his sacking in 2014, Moyes has failed to win any of his seven games against United in all competitions, losing five of those.

However, in-form Ronaldo has a mixed record against West Ham.

The Portugal star was involved in six goals in his last four league appearances against them in his first spell in England (five goals, one assist), though he also suffered three top-flight defeats to the Hammers.

Only against Chelsea (four) has Ronaldo suffered more Premier League losses than he has against West Ham.