What we witnessed before the astonished gaze of every Geordie was a throwback. A flick of the switch into reverse. Yesterday became today.

It had been a tale of two Citys . . . the one Pep built and won five Premier League titles, four Carabao Cups, two FA Cups, the Champions League, UEFA Super Cup, and FIFA Club World Cup. And the recent one riddled with self doubt and trailing Liverpool, Arsenal and incredibly Nottingham Forest in the chase for CL qualification.

Geordies travelled with a light heart and jaunty step. United had won 12 of their last 14 matches while Manchester City had unbelievably lost 12 out of 24. The Mags were chasing their seventh successive away victory, City chasing respectability after too many humiliations.

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So what happened? A passive United became what they once were in the bad old days and lost for the 16th successive time in the blue half of Manchester whereas City went back to an old and obvious scoreline: a 4-0 comprehensive win. United lucky to get nil.

The first feeling was one of abject disappointment. The next frustration at an opportunity lost. And finally indignation that the Toon Army's travelling hordes and those left on Tyneside to follow progress excitedly any way they could had been sold drastically short by their heroes. Losing is one thing, surrender quite another.

When the Mags are not at it 100 per cent in everything all of them do they get badly caught out. They cannot paper over cracks, get carried by the few. When it is good it is very, very good but when it is below par it can become unacceptable Alarmingly United lacked fight and character. If many are already tiptoeing towards the Carabao Cup final then heaven help us.

The match had been trumpeted as Alexander Isak vs Erling Haaland for the title of Europe's top striker. Isak had scored 17 league goals in 22 games this season, with five assists, compared to Haaland's 19 goals and two assists in 24 appearances. Yet it turned out to be anything but a Tyson Fury-Oleksandr Usyk punch up for king of the ring.

A guy who had never scored for City, new signing Omar Marmoush, smashed a first-half hat-trick and City's other winger Savinho smashed Lewis Hall. It was certainly not an occasion for Newcastle's two England international full-backs, Kieran Trippier and Hall, to showcase their talents. Trippier got hooked at half-time along with Joe Willock, the ultimate humiliation at 3-0 down with another 45 minutes on the rack to come.

However they were hardly alone in their abject surrender. When a teenage sub Lewis Miley shows United's blue chip players how to fight and care and have a go then it is a sad day. Maybe Trippier and Willock got subbed early doors and Hall's lack of defensive nous was exposed just as it was by Mo Salah up here in the second half against Liverpool but then where was the leadership of Captain Bruno, where was Sandro Tonali who had probably his worst game, where was the bounce and bravery of Anthony Gordon, the composure of Fabian Schar? If they all accept deserved plaudits during a long winning run then they ought to accept the flak when falling way below accepted standards. It wasn't a matter of being off form, it was a matter of easy surrender.

Marmoush had a record that ought to have warned Newcastle. He had plundered 15 goals in 17 Bundesliga matches for Eintracht Frankfurt before signing for City on the 23rd of last month and here he introduced himself to his new adoring fans with a trio of finishes in a golden quarter of an hour. A new Egyptian King has arrived in the Premier League. He cost City £59m of their £180m splurge in the January transfer window. Anything to be learned there United even with financial fair play rules to consider? We haven't spent a bent penny in the last three windows.

United have no midfield replacement of impact for Joelinton who was badly missed as was Sven Botman. Willock, his career admittedly ravaged by injury, has been strangely lightweight this campaign and any hope that FA Cup goals against League One opposition would spark confidence and a return to effectiveness was blown away by half-time.

United were the team with a free week to build up towards this crucial match while City had a mammoth and mentally draining Champions League play-off with Real Madrid in midweek but you would never have guessed it.

That it was a wake up call is obvious but will United have woken up by the time Forest come to test their mettle at the weekend? Or are they to sleep walk to Wembley with all that tells us? It is up to every single individual performing in front of supporters not easily fooled to prove they are fully committed physically and mentally against Forest.

To try and cruise towards Wembley is not acceptable or an attitude to bring any sort of positive results. It would mean sacrificing Europe which is the promised land all wish to walk upon and it would almost inevitably mean defeat in the Carabao Cup final because form is never a tap easily turned off and on. Finally it doesn't guard against what it is intended to and that is avoid injury which could wreck an appearance on the big day. So it is lose, lose and lose.