Sir Bobby Robson adored both of these clubs but, in their first Premier League meeting since his passing, it was Newcastle whose display would have made the old master’s eyes twinkle. A second four-goal victory in the space of a week suggests that, even allowing for their opposition’s failings, they are clicking into serious form. Sterner tests will come but, as advertisements for their attacking gifts go, this was enough to set Geordie mouths watering over Christmas.

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In Alexander Isak they have one of the most thrilling talents around and arguably the division’s most varied finisher. It does not always click for the Swede but a hat-trick here, the first from a Newcastle player for five and a half years, was taken with the panache of a player on top of his game. Isak has scored nine in his last nine top-flight appearances; when he is on song Eddie Howe’s team rightly feel capable of anything.

“He’s a world-class talent,” Howe said. “He’s got that coolness and composure in front of goal that very few strikers have. When you add how quick he is and how technically gifted he is, for me he’s got it all.”

He was certainly given the platform to show it. Put bluntly, this was men against boys. It was Ipswich’s most chastening defeat of a season in which they have run almost everyone close and, if this proves the worst things get at Portman Road, then perhaps their relegation battle is not ill starred. But they were barely involved amid teeming rain, beyond an improved 10-minute spell before Jacob Murphy thrashed in Newcastle’s second, and a productive January transfer window looks essential for the chances of a squad whose thinness was exposed here.

The tone was set within 26 seconds when, after a long Fabian Schär pass sent Murphy beyond Cameron Burgess, Ipswich failed to clear the resulting cross and Isak hammered a bouncing shot past Aro Muric. The flag went up for what seemed an offside against Murphy, but VAR divined at length that he had timed his dart well. It was no way for the home side to start but Newcastle could revel in picking them off from there.

More could have followed quickly, Anthony Gordon missing a header and Isak letting Muric save when clean through. Ipswich flickered when Martin Dubravka had to block from Sammie Szmodics but found many of their brighter moments snuffed out by Sandro Tonali, who was impeccable at Newcastle’s midfield base. Just after the half-hour Murphy, a Norwich academy graduate who enjoyed himself throughout, finished emphatically after Gordon had shuttled across the box and the outcome was essentially set.

“We’ve got to learn lessons and learn them really quickly,” said Kieran McKenna, who felt his players’ game management had been inadequate. Instead of regrouping they opened up and teemed forward, but only one team on show was going to win an attacking shootout. He saw that as a bigger issue than the manner of Newcastle’s third goal, which came when Muric played Jens Cajuste into a tight spot and saw Bruno Guimarães stick a toe in, giving Isak an unmissable chance.

Sections of the home support voiced their discontent at half-time. It is a vanishingly rare occurrence at McKenna’s Ipswich and failed to appreciate the context in which they were operating. If facing the power of a nation state-funded opponent was not enough, they were without a fully fit centre-forward after suspension to Liam Delap and a medium-term injury to George Hirst. That meant Szmodics, a buzzy attacking midfielder, was tried up front but they lacked the physicality to threaten and Muric had no real outball.

By the end those who remained were in louder, more defiant voice. It had long since become an afternoon for them to make the best of, Isak prodding an inventive fourth with no backlift after Murphy’s backheel. “I’m surprised it’s taken him this long to get a hat-trick,” Howe smiled. The recent revival of Murphy was another element that pleased the manager afterwards. Gordon and Joe Willock could have added more but Newcastle could stop at four.

In the two hours preceding kick-off queues had formed by the statue of Robson, draped in a half-and-half scarf for the day, that stands behind this venue’s east stand. A helpful steward obliged those waiting for photographs. What would Robson have thought of the ensuing rout? “I think he’d have been proud of both teams’ efforts,” Howe said. Only Newcastle, though, could depart feeling buoyant.

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