Erik ten Hag had hoped Mason Mount would be an emblematic figure. So he has proved; just not in the way the Manchester United manager intended. “He is a symbol of our season,” he sighed. In a year of over 60 injuries, Mount has contributed more than his share. He made his first start since November on Monday. He is injured again already. There will be no reunion on Sunday with perhaps his best mate in football.

Mount and Declan Rice is a friendship that began when they were eight and is sufficiently close that they have holidayed together. It started at Chelsea, a club only one was to play for. Rice was released as a teenager, rehabilitated when snapped up by West Ham. A decade on, he remains a rising force: the most expensive Englishman ever, at £105m, the runner-up in the Footballer of the Year vote, perhaps a Premier League champion next week. There was a time, however, when Mount looked the dominant figure in the double act: in 2021, he set up the winning goal in the Champions League final. He was Chelsea’s double player of the year: one in a season when they conquered Europe, one when they won the Club World Cup.

When Boehlynomics dictated his sale last summer, there was interest: from Arsenal and Liverpool as well as United. Perhaps Mikel Arteta’s obsessive attention to detail would have benefited him, maybe Jurgen Klopp’s feelgood factor would have done. Instead, he looks a casualty of the chaos at Old Trafford; possibly the face of Ten Hag’s failure in the transfer market.

There is a blend of misfortune and mistake; Mount has suffered from the first and the harsh conclusion may be that he is the last. “He is very unlucky,” said Ten Hag. In a campaign where there have been massive holes in United’s midfield, the treatment table has been overpopulated. And yet United had reasons to believe Mount would be a guarantee of games. “He is a very robust player,” Ten Hag insisted. “You see in his profile. In his last four seasons [at Stamford Bridge] he had only a small issue at the end of his Chelsea career. Before that he played almost all the games. Even with three days’ turnaround, he always played.”

Now he has hardly played any. Mount was injured after a week of first-team football, Ten Hag’s new midfield strategy destroyed on the opening night. An attacking midfielder was signed when it was soon clear they needed a more defensive one. The idea that Mount and Bruno Fernandes could be twin high-pressing No 8s had a fatal flaw: Wolves exploited it, finding space, isolating an ageing Casemiro, having 23 shots. It might be an oversimplification to say United have never recovered – they did win the game – but it suggested Mount and Fernandes are incompatible; at least if neither is to play as a winger, and the Englishman lacks the dynamism the Dutchman demands on the flanks. Then Kobbie Mainoo emerged to underline the impression that Mount is United’s £55m misfit; there is no space for him in their strongest side. While he will be fit for the FA Cup final, he is unlikely to begin it. His start at Palace only came because of that rarity, a Fernandes injury. Symbolically, United lost 4-0 and, while there are plenty to choose from, Ten Hag pronounced it their lowest point of the season.

That Sofyan Amrabat, the other midfield addition, has been wretched suggests United bought the wrong half of an old friendship. Rice is faster and fitter than Casemiro and Christian Eriksen, more accustomed to life behind the ball than Mount and Fernandes, more battle-hardened than Mainoo, better than Scott McTominay. “He is a very good player and he absolutely would have fitted in here,” Ten Hag said, perhaps imagining a parallel universe where Rice was paired with Frenkie de Jong in the United midfield. In the real world, he is a player whose first Arsenal goal came against United, who might have always chosen the Gunners anyway, who Ten Hag both could and could not afford.

Because he spent £63m on Casemiro and £85m on Antony the previous summer, because United wanted to divide their 2023 budget several ways rather than forking out for £100m signings. Unlike Manchester City, they did not enter the auction for Rice. United still ended up spending some £180m on Andre Onana, Rasmus Hojlund, Mount and Amrabat. The Danish striker made a promising debut in September’s 3-1 defeat to Arsenal and has since scored 14 goals. The goalkeeper has made plenty of saves but rather too many mistakes. So far, however, none really qualifies as a success.

Whereas, with the exception of the injured Jurrien Timber, all of Arteta’s summer signings do. Rice’s impact was immediate, though it took longer for David Raya and Kai Havertz to win over their doubters. That will be Mount’s task in his second season at Old Trafford, when the audience who require persuading may include a new manager. For now, however, Ten Hag remains adamant he was right to sign him. “I am very happy with Mason,” he said. “He is a good player. We really missed him across the season because he absolutely would have made a contribution to our levels.” And instead he has symbolised a season gone wrong for United.