In terms of learning curves, Marcus Rashford's career so far has resembled a young boy being given a racing bike, immediately winning a stage on the Tour de France, and only then someone arrives to attach some stabilisers.

Rashford's astonishing start to life at Manchester United last season was so spectacular that some form of regression this term was inevitable. That regression has taken the form of reduced playing time, Zlatan Ibrahimovic taking the bulk of the goal-scoring duties, and indeed rather less success in front of goal. Rashford hasn't scored a league goal since September, 961 barren minutes, give or take, over 18 appearances, with only three strikes against Championship opposition in the FA Cup to show for his efforts.

This season is probably close to how Rashford would have been treated had his introduction to the Manchester United first team been by design, rather than necessity. Thrown in because Louis van Gaal literally had nobody else last season, his initial form was a glorious, unexpected bonus. He scored goals, he showed an awareness that seemed absurd for someone so young, and reduced seasoned defenders to clueless head-scratchers.

Middlesbrough 1 Manchester United 3 player ratings Show all 22 1 /22 Middlesbrough 1 Manchester United 3 player ratings Middlesbrough 1 Manchester United 3 player ratings Victor Valdes – 5 out of 10 His double save was a moment of excellence, but he was beaten twice by Fellaini and Lingard and conceded a calamitous third. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Antonio Barragan – 5 out of 10 Held his shape well at the back, but was beaten by the occasional over the top ball. Getty Images Middlesbrough 1 Manchester United 3 player ratings Bernardo Espinosa – 3 out of 10 Really struggled against the pace of Rashford and the other United forwards. An afternoon to forget. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Ben Gibson – 5 out of 10 Tried in vain to start attacks by hitting long-passes forward but had a difficult afternoon. Getty Images Middlesbrough 1 Manchester United 3 player ratings Fabio – 6 out of 10 Looked assured in possession and did well going forwards; one of Middlesbrough's better players. Getty Images Middlesbrough 1 Manchester United 3 player ratings Marten De Roon – 5 out of 10 He worked relentlessly, but ultimately failed to make an impact on the game. He was outplayed in the midfield. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Adam Clayton – 4 out of 10 He looked lost at times – drifting in and out the game. Lost possession quickly and failed to read the game. Man Utd via Getty Images Middlesbrough 1 Manchester United 3 player ratings Grant Leadbitter – 6 out of 10 Was a key element to almost every Boro move – making clever and quick decisions in possession. Getty Images Middlesbrough 1 Manchester United 3 player ratings Stewart Downing – 5 out of 10 Wasteful in possession and failed to make an impact going forward. Getty Images Middlesbrough 1 Manchester United 3 player ratings Alvaro Negredo – 5 out of 10 Was Middlesbrough's principal target man but he was always surrounded by a sea of United shirts. Getty Images Middlesbrough 1 Manchester United 3 player ratings Gaston Ramirez – 6 out of 10 Caused a nuisance of himself, but was guilty of dropping too deep at times. Getty Images Middlesbrough 1 Manchester United 3 player ratings David De Gea – 5 out of 10 Had very little to do. Unfortunate with Middlesbrough's goal. Getty Images Middlesbrough 1 Manchester United 3 player ratings Eric Bailly – 5 out of 10 Ramirez was getting the better of him at times due to his slack man-marking. Getty Images Middlesbrough 1 Manchester United 3 player ratings Chris Smalling – 6 out of 10 Intercepted a handful of important crosses and led the United defence well. Could have done better to clear the ball for Gestede’s goal. Getty Images Middlesbrough 1 Manchester United 3 player ratings Phil Jones – 5 out of 10 Held his own at the back, but made a number of unnecessary fouls. Getty Images Middlesbrough 1 Manchester United 3 player ratings Ashley Young – 6 out of 10 His assist for the opening goal was an example of his ability, although he drifted out of the game late on. Man Utd via Getty Images Middlesbrough 1 Manchester United 3 player ratings Michael Carrick – 6 out of 10 A textbook Carrick display. He created chances, defended well and his work rate was relentless. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Marouane Fellaini – 7 out of 10 Opened the scoring for United with a header. Tough tackling and used possession well throughout. Getty Images Middlesbrough 1 Manchester United 3 player ratings Antonio Valencia - 5 out of 10 Defended well, but looked even better going forward to support the strikers. Getty Images Middlesbrough 1 Manchester United 3 player ratings Juan Mata – 7 out of 10 Looked dangerous going forward and classy on the ball. Getty Images Middlesbrough 1 Manchester United 3 player ratings Jesse Lingard – 7 out of 10 His goal was an example of his individual ability – fully deserved. He linked well with Rashford throughout. Getty Images Middlesbrough 1 Manchester United 3 player ratings Marcus Rashford – 6 out of 10 Should have scored, especially in the first half. Worked well, but needs to be more clinical. AFP/Getty Images

Under Jose Mourinho, he has been used more sparingly, perhaps appropriately for a forward who is still only 19, but Ibrahimovic's suspension for the trip to Middlesbrough theoretically represented a chance for him to beef up that goal-scoring record. That, he didn't manage, and indeed he didn't take a couple of extremely presentable chances to do so. Nevertheless, after the match Mourinho volunteered plenty of praise for his young striker.

“Marcus is a completely different player than Zlatan,” said Mourinho. “We have to adapt to his qualities. It's really difficult for him to score a goal [at the moment], but his movement is top class, second to no-one. So intelligent, so sharp, the first touch to put the ball in the best position to attack the space. For me, he played phenomenal.”

There was a slight hint of how Mourinho reacted to Paul Pogba's bad showing against Chelsea last Monday in this: the ostentatious puffing up of a player who he thought might be about to receive some criticism, heading that off at the pass while also trying to give his player some confidence. In this sort of situation, it doesn't really matter if the praise is true or not: if there's a chance that the player will either believe or be encouraged by those words, it's worth saying them.



On this occasion though, it was a little easier to take what Mourinho said at face value. Rashford's pace and dynamism sliced holes in the Middlesbrough defence at will, centre-back Bernardo in particular given an afternoon he might want to forget, but will probably remember in nightmarish flashes for years to come.

In the first-half particularly, Rashford looked like United's most dangerous threat, his movement not only creating chances for himself, but space for others. For a United team not overloaded with pace, Rashford gives the whole team more options, and makes it more varied and unpredictable. "I always play well with Marcus," said goalscorer Jesse Lingard after the game. "He’s put in a shift for the team today and made a nuisance of himself; again he has proved that he is a good player."

That Rashford sometimes didn't make the most of the situations he created should not be a surprise. He only turned 19 in October, an age at which only the tiniest fraction of players have ever been a polished player: we have to remember that we are watching a kid learning on the job, rather than a fully formed adult putting years of study into practice. Even the chances he “missed” against Middlesbrough were down to excellent saves by Victor Valdes.

Ibrahimovic has one more game of his three-match suspension to serve, but after that Mourinho must figure out the best way to get both he and Rashford in the same team, for the different threats each provide. Previously this has involved the younger man playing on the wing, but might a strike duo be an option? It could also be a solution to another problem: a 3-5-2 system, with Rashford and Ibrahimovic up front and Paul Pogba part of a three-man central midfield, the set-up in which he often excelled with Juventus, might work very nicely.