Erik ten Hag makes his point as under-fire boss inspires Man Utd to stunning FA Cup win over Man City

Erik Ten Hag was bullish about his future, even as the rumours of his supposedly imminent sacking intensified this week. Maybe he knew something others didn't. Manchester United saved their best performance of the season for the game that mattered most.

It remains to be seen whether this stunning, trophy-winning end to an otherwise fraught campaign will be enough to save him. It was not enough for Louis van Gaal in 2016 and his team finished fifth, three places higher than Ten Hag's, in the Premier League table.

But it certainly makes his case more compelling. Watching the delirious United celebrations after the final whistle in isolation, all the sweeter for having denied their rivals another double, it was difficult to fathom that this could be his final game in charge.

Not that all that came before this should be forgotten.

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It has, until now, been a desperately poor campaign, a campaign in which United slumped to their lowest finish of the Premier League era, in eighth, with their second-lowest points total. Results have been dismal; performances, for the most part, even worse.

And yet here we are. At the end of it all, Manchester United are deserved FA Cup winners, securing a place in next season's Europa League and making it two trophies in two years under Ten Hag, this one following last season's Carabao Cup triumph over Newcastle.

The Dutchman had been at pains to draw attention to his injury list over the course of the season. Here, he welcomed back Marcus Rashford, with Raphael Varane fit enough to partner the returning Lisandro Martinez for only the sixth time all season in defence.

Their contribution was immense. Martinez and Varane got heads and boots to everything City threw at them. Rashford, meanwhile, gave a timely reminder of his huge talent following his England snub, proving a constant threat in behind, his swagger restored.

But this Manchester United triumph was not just down to returning personnel. It was tactical too. Their biggest problem this season has been the glaring openness of their midfield.

Its components here - Kobbie Mainoo, Sofyan Amrabat, Scott McTominay and Bruno Fernandes - have been available and free of injury for most of the season.

And yet, this time, those previously open spaces were squeezed, the compactness of United's midfield four, supported by Rashford and Alejandro Garnacho, leaving City with no route to goal.

Varane and Martinez defended heroically but unlike in previous games, United's centre-backs had protection too. It is reasonable to wonder why the gaps were left open for so long. How different United's campaign might have been had Ten Hag struck upon the formula sooner.

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Only relegated Sheffield United gave up more shots than them in the Premier League this season. But at half-time, with Ten Hag's side two goals to the good, the damage done, they had only allowed their opponent - this opponent - two efforts on goal.

That number had increased to 19 by the end of the second period but that was to be expected given the circumstances. As City ramped up the pressure and United's backs were pressed against the wall, they battled through. City's breakthrough came too late.

This was the champions' first domestic defeat since early December and their first in 74 games with linchpin Rodri starting.

Guardiola's substitutions told a tale.

At half-time, a double change saw Nathan Ake and Mateo Kovacic come off for Jeremy Doku and Manuel Akanji. Before the hour-mark, Kevin de Bruyne's number came up for Julian Alvarez. The Belgian, unstoppable in recent months, had been completely nullified.

Amrabat was key to that, the Moroccan putting a difficult campaign behind him and delivering by far his best display for United, anticipating danger, shutting off passing angles diligently and using the ball smartly too, misplacing only two out of 27 passes.

It was the player next to him, though, the 19-year-old Mainoo, scorer of their brilliantly-worked second goal, whose performance will satisfy Ten Hag the most.

Mainoo took his goal brilliantly, the headline contribution of a player-of-the-match display, but he was outstanding in all areas. "You look at his composure on the ball, little passes, one-twos," said a watching Wayne Rooney, "I think he's got everything."

Ten Hag has given his critics plenty of ammunition over the course of the season but he deserves credit for Mainoo's stunning emergence and he has displayed similar levels of trust in their other scorer, Garnacho, who pounced for the opener and had a hand in the second too, feeding Fernandes to set up Mainoo.

The pair are the first teenagers to score in an FA Cup final since Cristiano Ronaldo in United's victory over Millwall in 2004. It is another factor which strengthens Ten Hag's case to stay as they look towards the future under Sir Jim Ratcliffe.

"I don't think about this," Ten Hag said when asked whether he expects to stay on afterwards. "We are exactly where we want to be. We are constructing a team. When I took over, it was a mess at United. The team is developing and winning trophies."

It remains to be seen whether the club's part-owner sees things in the same way. For now, though, this manager and his players can simply savour a success few anticipated, and a trophy-winning end to a turbulent season. Ten Hag has made his point.