After a victory that secured Manchester United third place on 75 points Erik ten Hag offered what could be read as a dig at the hierarchy for failing to back him in the January transfer window.

Then, Liverpool bought Cody Gakpo (for £37m), Newcastle recruited Anthony Gordon (£45m), and Chelsea splurged £320m-plus on eight players including Enzo Fernández and Mykhailo Mudryk. Yet after Cristiano Ronaldo’s departure during the World Cup and Christian Eriksen’s serious injury in January, Ten Hag secured only loans for Wout Weghorst and Marcel Sabitzer.

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Ten Hag was asked about his summer recruitment plans. “The club knows if you want to play top four, compete for trophies in this tough league, then you have to invest, otherwise you don’t have a chance because other clubs will do,” he said. “We’ve seen it in the winter: all the clubs around us made huge investments, we didn’t, but still we made it, so I’m proud of my team.

“We are in the right direction, but we are not where we have to be. There’s potential in this team and in individual players. We showed during the season we made progress; that’s a compliment to the players and the coaches. We worked really hard but we have to make an investment.”

Ten Hag now switches focus to beating Manchester City in the FA Cup final on Saturday and halting the tilt of United’s neighbour at emulating Sir Alex Ferguson’s 1999 vintage by claiming the treble. The aggregate score this term between them and City is 7-5 in the champions’ favour, though this hides the 6-3 trouncing United took at the Etihad Stadium in October.

Ten Hag said: “You always have a chance in football. History shows we beat them in January and that Man United in the last couple of years beat City many times. So these players know when they play at their levels they can compete. It’s obvious we play against the best team, but there is a chance and we have to go for the chance and give everything. We can’t find excuses for ourselves after the game. I’m sure we will play a good game.”

The Dutchman can enjoy a boost, too, from a defeat of Fulham that showed spirit, energy and 110mph football that may be the best hope of overcoming the champions at Wembley. They may also have Antony after Ten Hag revealed that the winger “probably will be available”.

As all season here, the game was contested in the noisy atmosphere which is the corollary of an entertainment factor under Ten Hag that on Sunday featured a comeback win.

Kenny Tete gave Fulham the lead after David de Gea’s latest failure to make an aerial contribution when required. Willian pitched in a corner from the left and up rose the Fulham right-back unchallenged (Marcus Rashford headed air), Tete squeezing the ball home at the near post.

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If this was not brilliant from De Gea, the next act was. Harry Maguire – possibly in a last Old Trafford outing for United – had a pass intercepted and when Tom Cairney skipped right in the area Casemiro fouled him and Robert Jones awarded the penalty. Aleksandar Mitrovic hit this to De Gea’s left and the Spaniard dived low to make a fine save, his first here from the spot since a Leighton Baines effort in 2014.

De Gea is usually poker-faced but he celebrated, as did his colleagues and the delighted home crowd. Inspired, United rushed up the other end and had a couple of chances. In a lightning move, Diogo Dalot robbed Willian and tapped to Casemiro, whose weighted ball allowed Rashford to feed Fred, who found Bruno Fernandes. The Portuguese’s instant pass (the fifth of the sequence) played in Alejandro Garnacho, who could not score. Even closer was the chance engineered when Tyrell Malacia side-footed again to Garnacho and the youngster crashed his shot off Bernd Leno’s bar.

United were behind yet ebullient and their mood was about to skyrocket. Fernandes adores leading the charge and for an umpteenth time the No 8 created a goal. The key part was holding off Sasa Lukic which, after a twirl, was followed by possession being stroked to Fred. As the Brazilian pulled the trigger he was caught in a Tosin Adarabioyo-Tete sandwich, the ball ricocheted to Jadon Sancho, who rolled in the equaliser.

The last time this fixture was staged here (in the Cup in March) Fulham self-combusted in 40 seconds of madness featuring three red cards that were superseded by Fernandes scoring a penalty to level the score. Now, his goal gave United three points and he could thank Fred, who fashioned a defence-bisecting pass that allowed Fernandes to dink home.