The Magpies cruised to a record-equaling 8-0 victory in their reverse fixture at Bramall Lane, yet as they did against Manchester United in midweek, the Blades took a surprising lead.
Perhaps playing with a degree of freedom knowing that their PL fate was all but sealed, Sheffield United put their hosts under pressure from the off and found an early breakthrough when Anel Ahmedhodzic’s header from Gustavo Hamer’s floated cross squirmed under Martin Dubravka to silence the Toon Army.
It was all-action at St James’ Park, with Cameron Archer denied by Dan Burn’s block before Longstaff saw his close-range shot thwarted by Auston Trusty.
Newcastle restored parity minutes later as Jacob Murphy’s through-ball found Alexander Isak, who kept his composure to score for a seventh successive home match with a low finish past Wes Foderingham.
Chances continued to come, as Ben Brereton Diaz was denied by a last-ditch Burn slide and Foderingham was called into action on the stroke of half-time to deny Lewis Hall from range.
Newcastle hauled themselves in front minutes after the restart thanks to a floated Anthony Gordon set-piece delivery to the back post, where Bruno Guimaraes was on hand to convert with a diving header.
Brereton Diaz had a chance to equalise soon after but a third Newcastle goal then killed off the Blades’ fightback
Mason Holgate brought down Gordon in the box, allowing Isak to convert from the spot – his 23rd goal of the season - and the wheels then came off for the visitors with relentless Newcastle attacks adding a fourth goal via a Ben Osborn own goal before substitute Callum Wilson’s fierce strike made it five.
A late penalty award in Sheffield United’s favour was overturned as their immediate return to the Championship was confirmed, with a bottom-placed finish all but guaranteed in what is ultimately a very disappointing campaign for the Blades.
Meanwhile, a win keeps Newcastle in the hunt for Europa League football, one point off sixth place after recovering from a 2-0 defeat to Crystal Palace in midweek.
Flashscore Man of the Match: Dan Burn (Newcastle United)