Ruud van Nistelrooy always promised goals for Manchester United. There were 36 in his first season as a player, 44 in his second. There were seven in his first game as their interim manager, five of them for United. The third-lowest scorers in the Premier League, United discovered a prolific streak under him. If it is to prove his lone evening in charge of United, what a night for him.

It was a nostalgia trip when Van Nistelrooy headed down the tunnel at half-time to be serenaded by the Stretford End. The choruses of his name, the guttural growls of “Ruud”, may have transported them back to 2003, to a happier time, and if United can forever seek solace in their past, when actually needing to escape it, this was an enjoyable interlude before Ruben Amorim’s tenure begins, assuming it does and depending on when it actually starts.

United have been here before, with Ryan Giggs and Ole Gunnar Solskjaer and Michael Carrick, who all won as caretakers, who all – sometimes briefly – restored a feelgood factor. There was another comeback: Sir Alex Ferguson was present for the first time since it was announced he is to lose his lucrative ambassadorship, his presence conferring a seal of approval to another of his former players, albeit one he first signed and then ruthlessly sold. The old-fashioned, end-to-end entertainment offered a throwback to Ferguson’s days.

Sadly, for a more recent United manager, it was the sort of occasion to suggest a sacking was entirely justified. Erik ten Hag argued all his side needed were goals, and his feeling he was luckless may have been exacerbated as they arrived in a flurry for Van Nistelrooy, but the reaction he generated was damning of the dismissed Dutchman. A liberated team looked happier and attacked. Their new-found confidence was apparent when the substitute Amad Diallo almost scored with a spectacular overhead kick.

Braces for Casemiro and Bruno Fernandes evicted Leicester from the Carabao Cup. Ten Hag, in a final moment of delusion and ignoring the reality United are 14th in the Premier League, had declared their season would be a success if they won it. They are a step closer to doing so, presumably with three managers in the competition in as many rounds.

Van Nistelrooy is only a temporary appointment but he made an impression. He looks like a manager, his smart dark coat a contrast to Ten Hag’s trademark gilet. He was a towering, statuesque figure on the edge of the technical area, hands planted in pockets.

He was, though, punching the air in disbelief at the opener. Casemiro scored the last goal of the Ten Hag reign and the first of the Van Nistelrooy interregnum, curled in gloriously from 25 yards. Goalkeeper Danny Ward barely moved. Van Nistelrooy reacted more joyously; he scored 150 goals for United, but perhaps none this good. As only one came from outside the box, this was not his range. “An absolute beauty from Casemiro,” Van Nistelrooy said.

It was, though, an early clue that this was the antithesis to the dog days of the Ten Hag years. Diogo Dalot missed an open goal in the former manager’s final game; here, Casemiro scored in outlandish fashion. Fernandes had not found the net in his last 17 appearances under the manager who made him captain. He promptly got two goals in the first game after his departure. Ten Hag complained about VAR’s intervention at West Ham, for Jarrod Bowen’s decisive penalty. This time, technology was not used and the grievances belonged to Leicester when Alejandro Garnacho swept in the second goal after a cross from the seemingly offside Dalot. “A terrible linesman’s decision,” moaned Steve Cooper.

“All of a sudden we had some luck,” said Van Nistelrooy. If fortune may not have favoured Ten Hag at the end, it benefited Fernandes when his drought was ended as his free kick took a huge deflection off James Justin’s head. His second goal was both gift-wrapped and classy, the Portuguese latching on to Caleb Okoli’s back pass, strolling around Ward and taking his time before walloping the ball into the net. Before then, Casemiro, the talismanic figure in Ten Hag’s 2023 Carabao Cup final win and a more troubled one for much of the subsequent 18 months, had his second, burying the rebound after he had headed Marcus Rashford’s cross against the post.

Such notes for concern for Amorim, when he surveys the footage, may come from how open United were. Van Nistelrooy kept his predecessor’s 4-2-3-1 formation but Altay Bayindir, only given one United appearance by Ten Hag, doubled his tally and conceded for the first time in their goal. Bilal El Khannouss drilled in a lovely strike with the outside of his right foot. Conor Coady scored from close range after Dalot contrived to chest a free kick straight to him. Leicester were spirited, with Boubakary Soumare rattling the bar. But United were vibrant, victorious and Van Nistelrooy’s boys.

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