Jose Mourinho has admitted Marcus Rashford has experienced a “very difficult” second season for Manchester United but has challenged him to recapture his best form next season.

Rashford burst onto the scene under Louis van Gaal after United suffered a striker injury crisis and went on to score eight goals in his first 18 games for the club, as well as netting on his England debut and featuring at Euro 2016.

However, the 19-year-old has struggled during his second season in the senior team and has only managed seven goals in 36 appearances for United this term and has found himself out wide or used as an impact sub by Mourinho.

Rostov vs Manchester United player ratings Show all 11 1 /11 Rostov vs Manchester United player ratings Rostov vs Manchester United player ratings Sergio Romero - 5 out of 10 Could have stood much taller against Aleksandr Bukharov and perhaps prevented the goal. Rostov vs Manchester United player ratings Chris Smalling - 4 out of 10 Almost as culpable as Jones for the goal. Some simple communication between the pair would have prevented Rostov’s goal. Rostov vs Manchester United player ratings Phil Jones - 4 out of 10 Cost his side when he failed to track Bukharov's run over his shoulder. Too easily beaten by the long ball out the back. Rostov vs Manchester United player ratings Marcos Rojo – 6 out of 10 United’s best defender, though that is not saying much. Produced an important, last-ditch tackle to deny Rostov on the break late on. Rostov vs Manchester United player ratings Ashley Young - 6 out of 10 Showed purpose from wing-back in the first-half but ultimately lacked a telling end-product. Rostov vs Manchester United player ratings Daley Blind - 5 out of 10 Left with too much responsibility as a lone man on the left flank. Struggled to offer United the width they required to penetrate. Rostov vs Manchester United player ratings Marouane Fellaini - 7 out of 10 One player who suited the adverse conditions underfoot and repeated balls over the top. Combined his physicality with a rare bit of technique in the build-up to Henrikh Mkhitaryan's goal. Rostov vs Manchester United player ratings Ander Herrera – 5 out of 10 Game for the rough tackling that defined the first half hour but offered little more. Rostov vs Manchester United player ratings Paul Pogba – 4 out of 10 Failed to impose himself on a game once again. Jose Mourinho is trying to play him into form but he remains some way off. Rostov vs Manchester United player ratings Henrikh Mkhitaryan – 7 out of 10 A promising return to the side, curtailed by his second-half substitution. There at the right place at the right time to put away the opener. Rostov vs Manchester United player ratings Zlatan Ibrahimovic – 6 out of 10 A sublime assist for the opener, then too quiet after it, but rarely received service in the right areas.

Rashford is set to miss United’s FA Cup quarter final with Chelsea on Monday night through illness and Mourinho has revealed he always knew the striker wouldn’t hit the heights of his debut season again so soon.

"I knew that it would be a very difficult season for him after the season of the surprise,” the United manager said.

"The season without pressure, the season where nobody demands, that nobody knows him, he comes in and makes an impact, he feels free. He is just a kid that is enjoying his football.

Stormzy talks Manchester United

"The second season was always going to be a difficult one.

"I think the third season is going to be the good one again. The third season is one with more maturity, he can build on his experiences so I am sure the third season will be better than the second.

"The second season is the difficult one. It's the pressure, it's the people that knows him, it's the expectation.

"Is he a national team player? Is he in the line-up for the club? Should he go to the Euro 21 [European Under-21 Championship] or no? Having all these things around him doesn't give him an easy season, but he is a good kid, a good humble boy, he tries to learn with every experience.