Nothing is ever simple for Erik ten Hag. The Manchester United manager, these days a perpetual firefighter, has been at pains to say he has the respect of his squad despite Marcus Rashford’s latest misdemeanour and, in fairness, nobody can argue his players are not with him after Kobbie Mainoo snatched victory in style with 96 minutes and 26 seconds on the clock.

Just as it seemed United, 2-0 up inside 22 minutes but pegged back to 3-3 after 95, had gone up in flames, they exploded into life and many of the substitutes on to the pitch after Mainoo, the 18-year-old from Stockport, displayed a handy fearlessness, swivelling clear of João Gomes, nutmegging Max Kilman, driving into the box and then caressing an effortless, right-foot strike low into the bottom corner.

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It all brought a beaming smile to the face of Sir Alex Ferguson, who was sitting alongside David Gill, the former United chief executive, in the directors’ box. Ten Hag, in a grey beanie, roared with relief but was largely unmoved, doubtless still stewing at how his side again crumbled and, for the fourth straight league game, conceded two goals.

Both sets of players, staff and supporters were incredulous. Nélson Semedo and Mario Lemina, crestfallen, were reduced to all fours. João Gomes covered his eyes as Mainoo and his United teammates cranked up the celebrations. It was a quite simply preposterous climax to a football match.

Wolves had been upping the ante from the moment Lisandro Martínez cleared a Kilman header off the line four minutes into the second half and replied from the penalty spot when Casemiro was deemed to have clipped Pedro Neto inside the box. Pablo Sarabia, the architect of Wolves’ incredible comeback win over Tottenham here in November, beat André Onana, who returned in the United goal after Africa Cup of Nations duty for Cameroon. Most presumed Wolves hopes of anything close to repeat were gone when the substitute Scott McTominay, unchallenged, headed in Bruno Fernandes’s corner on 75 minutes.

This United team are never too far from crisis, though, and Wolves roused again when Kilman stabbed in from close range with five minutes of normal time to play. At 3-2, Ten Hag sent on Harry Maguire and then Jonny Evans to bubble-wrap victory but then Neto streaked down the right flank, cut inside and rattled a shot inside Onana’s left post. United, bizarrely, had gone gung-ho in attack and their defence had gone missing, leaving Neto the freedom of Molineux.

For so long the obvious thing was to laud Rashford’s goalscoring return after his latest ticking-off from Ten Hag but, zoom out a little, and there were glimmers of something else stirring beneath the surface. For the best part of an hour, United made rather compelling viewing. Rashford and Rasmus Højlund capped slick team moves. Ten Hag acknowledged this was probably his strongest starting lineup of the season and a team brimming with World Cup and Champions League winners and a couple of the game’s brightest talents seemed to click.

Ten Hag insisted it was a matter of case closed when it came to Rashford and his unlicensed gallivanting in Belfast nightspots this time last week but, in reality, all eyes were on how the 26-year-old would fare on his return to the team. The answer was a resounding one, Rashford tormenting Semedo, Wolves’ right-wing back. Wolves, Gary O’Neil said, anticipated Rashford would start and so he did, which perhaps explains the pointed pre-match playlist that featured both The Champs’ and Terrorvision’s songs by the name of Tequila.

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Within 25 minutes, with United cruising at 2-0, the away supporters stretched across the bottom of the Steve Bull Stand saw the funny side of things, glorifying his latest disciplinary episode. “Rashford’s on the piss,” they cheered in unison.

Rashford was central to much of United’s good work and Casemiro and Højlund had a goal apiece disallowed for offside. The glaring caveat is that for the fourth league game running they conceded at least two goals, their grimly predictable vulnerable streak exposed. Sarabia struck from the penalty spot before Kilman further reduced the deficit. Rashford played 73 minutes before being replaced by Antony, by which point Wolves had got on the scoresheet, Sarabia sending his spot-kick down the middle after Casemiro, already booked, was penalised.

But United, as Ten Hag admitted, gave Wolves a leg-up. Once tested United, whose frailties were exposed by a middling League Two team last weekend, were easily ruffled. Martinez hacked Kilman’s header off the line and then Craig Dawson went tantalisingly close, his deflected shot skidding off Onana’s header and clear. Alejandro Garnacho celebrated nicking the ball from Mario Lemina on halfway like a third goal. In the end United required four to get the job done.