Jose Mourinho punched the air. Sirs Alex and Bobby applauded from the stands. Manchester United players formed a queue to congratulate the man of the moment.

Of course, as celebrated as Bastian Schweinsteiger’s appearance as a second-half substitute against Reading was, the German was selfishly overshadowed. Wayne Rooney is his country and club’s record goalscorer.

He requires one more to surpass Charlton’s 249, of course, but the captain’s strike against Reading in the FA Cup third round kickstarted an afternoon of revelry at Old Trafford. Forget that the record-equalling goal came rather fortuitously off his knee; forget the standard of defence a Championship opponent posed; forget scoring two goals against Verona in the Anglo-Italian Cup in 1973; remember Rooney as an historic figure in English football.

It was a fitting way to equal the record. For a split second against Reading, the 31-year-old trusted not his ageing body, but his ageless mind. Juan Mata delivered a presentable cross, and the instincts of a teenage goalscorer took over. He stuck out a leg, diverting the ball beyond goalkeeper Ali Al-Habsi.

Few will argue with Rooney’s man of the match award, as representative of his career achievements as it was his performance. Having said that, he scored one goal, assisted another, had six shots, four on target and created five goalscoring opportunities. The years are too advanced to roll back, but this did serve as a reminder that he does still have a part to play. A bit part, but a part nonetheless.

This was not Rooney’s swansong, yet it did feel as though a symbolic torch had been passed to his successor. Many of the characteristics Rooney possessed in his earlier years – the driving runs, the pace, the strength, the goals – are now present in Marcus Rashford. The 19-year-old did not enjoy a faultless game, but on a rare start as a central striker, he impressed a buoyant crowd.

“I had lots of winning teams, we won in every club but we didn’t have many teams playing so well as my Man United team does,” Mourinho said before the game, and as his side secured their eighth successive victory, it was difficult to argue. Rooney, Rashford, Anthony Martial, Juan Mata, Michael Carrick – all were excellent, dominant, expressive. Reading could not cope.

There were the usual raking passes from one wing to another from Rooney, but they found their intended target. Mata and Rashford were impossible to mark, constantly interchanging. Martial was a wonder on the left-hand side. Even Marouane Fellaini displayed some delightful footwork in the second half. This is a confident United.

What’s more impressive is that this was, for all intents and purposes, a side in the mould of Louis van Gaal. Mourinho made nine changes, and the same number had started the FA Cup final against Crystal Palace in May. But there was no sterile domination, no aimless possession, no philosophy here. United were great.

Talk after the game will be of the past, with many choosing to reminisce over happier times for Rooney: The debut hat-trick against Fenerbahce, the overhead kick against Manchester City, the goals against Liverpool and Arsenal. But this was proof that the 31-year-old cannot be consigned to the history of the club just yet. He still has something to offer, albeit now as a squad player instead of a first teamer.

One of the main beneficiaries of his presence will be Rashford, the brilliant teenager learning from both Rooney and Zlatan Ibrahimovic, afforded a rare rest alongside Paul Pogba and Henrikh Mkhitaryan. Rashford ran the channels selflessly, pressed relentlessly, threatened constantly. His two goals were just reward, and represent his first since September.

Rooney will dominate the headlines and coverage of this game, and deservedly so. His best remains in the past, but he is still useful for United in the present. Rashford and Martial ensure that the future can be just as bright.

Matt Stead