Sheffield United are presumably relieved that their next league assignment in the north-east will be at Sunderland or Middlesbrough. Long before the final whistle brought confirmation of a relegation to the Championship that Chris Wilder had already deemed inevitable, his players had seen more than enough of Newcastle and the excellent and electric Alexander Isak in particular.

Thirteen of the Premier League goals scored by Newcastle this season have arrived against the Blades and the latest quintet, with two registered by Isak, enhanced their hopes of hosting European nights this autumn.

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Wilder seemed unsurprised. “It’s an incredibly young side and there’s a complete lack of leadership,” the Sheffield United manager said. “We haven’t been good enough. This l eague has been too powerful for us.

“We should have been 3-0 up at half-time rather than 1-1 but after that our old mistakes returned, nobody was brave enough to make the right challenges and the goals went in. There’s a reason for that. The gap between the Premier League’s haves and have-nots is huge now but some of our performances have been completely unacceptable. The mentality has to change.”

His challenge now is to put things right. “It’s going to be a tough summer. But I’ve got another year on my contract and I’d like to think the supporters trust me. I’ve got a desire to get it right next season.”

Although it was ultimately straightforward for Newcastle any notions that the first half might be a gentle canter were quickly debunked when the fallout from a short corner routine led to the unmarked Anel Ahmedhodzic heading Sheffield United into a surprise lead. The visitors were aiming to atone for their 8-0 home defeat in September and started the right way before eventually falling apart.

If that opening goal served as a reminder of Newcastle’s enduring vulnerability at set pieces at least they can rely on Isak. The Sweden striker’s 18th league goal of the season drew Newcastle level thanks to a beautifully calibrated right-foot from shot from Jacob Murphy’s fabulous through pass that left Wes Foderingham helpless .

Initially at least the visitors refused to fold and could count themselves slightly unfortunate not to equalise when Dan Burn blocked Ben Brereton Díaz’s shot after the striker had rounded Martin Dubravka and Mason Holgate’s effort rebounded off a post.

Captained by their 19-year-old central midfielder, Oliver Arblaster, and with Cameron Archer showing off some impressive attacking movement, the visitors, albeit briefly, seemed determined to show they could play a bit after all.

Arblaster is the seventh Blade to have worn the captain’s armband this season but he proved powerless to provoke a comeback when Brazil’s Bruno Guimarães demonstrated precisely why the release clause in his Newcastle contact is set at £100m by heading Anthony Gordon’s free-kick beyond Foderingham.

With Guimarães shining in midfield, Sheffield United suddenly had few answers to Newcastle’s questions. After Holgate sent Gordon tumbling in the area Isak – who, on this form, must be worth considerably more than that £100m – increased their lead from the penalty spot, Ben Osborn directed a backheel flick into his own goal and the substitute Callum Wilson used his right foot to score his side’s fifth.

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It was the 97th goal Sheffield United had conceded in 35 league games. They thought they had won a penalty when another home substitute, Alex Murphy, appeared to fell Jayden Bogle but a video assistant referee review prompted Tony Harrington to change his mind. It seemed a microcosm of Sheffield United’s season.

Newcastle had been rewarded for upping the second-half tempo after what Isak described as a “wake-up call” at the interval. It left Eddie Howe bombarded with questions about whether he can keep Isak and Guimarães on Tyneside. How Wilder would love to be confronted with similar problems.