JOSHUA King struck a dramatic 88th-minute winner to earn Cherries their first victory at Sunderland and send Eddie Howe's team soaring past the Premier League 40-point mark.

The striker swept home after Ryan Fraser, released down the right by substitute Lys Mousset, galloped forward and calmly crossed for King to plunder his 12th goal of 2017 – and 11th in 12 matches.

Sunderland's defeat condemns them to relegation, while it would now take a remarkable turn of events to deny Howe's men a third season of top-flight football.

The confidence Cherries had gained from last week's crushing victory over Middlesbrough was immediately apparent here. Indeed, the game was less than 60 seconds old when Charlie Daniels received his short corner back from Fraser to drift effortlessly past Steven Pienaar and fire a cross into a crowded six-yard box. Left-back Javier Manquillo scrambled the ball behind but, from the first whistle, the hosts' jitters had been evident in almost every element of their play.

By the time 15 minutes had elapsed the perennially disaffected home supporters were similarly anxious, their frustration raining down from the sparsely populated Stadium of Light stands after watching their side cough up possession for the umpteenth time.

In the intervening period Adam Smith had cantered forward to exchange a one-two with Fraser and square for King, who scuffed his shot low into Jordan Pickford's gloves.

King was then desperately close to getting his head on a terrific Fraser cross, the Scotsman allowed all the time in the world to deliver after another smartly worked corner involving Daniels and Marc Pugh.

Winger Pugh was in his element, picking up where he left off against Boro seven days ago and intent on turning Donald Love's personally difficult start to the afternoon into something particularly grizzly – the Sunderland right-back had twice needlessly gifted the ball to his opponents in potentially fatal situations during the opening exchanges.

Fabio Borini seemed to sum up the malaise sweeping through David Moyes's team when he miskicked hopelessly while attempting a 10th-minute shot.

The Italian's next effort, though, when he picked up the pieces after Jermain Defoe had been balked by Steve Cook, had rather more venom about it; Cherries' keeper Artur Boruc having to be on his mettle to parry away a wicked, swerving effort.

If that cheered the locals, then they were out of their seats again, anticipating something special, when Defoe swapped passes with Wahbi Khazri. From the edge of the box, though, the striker lifted his eventual effort high over the bar.

Cherries quickly returned fire – and King came agonisingly close to breaking the deadlock. Benik Afobe did the dirty work, strongly holding up the ball on the left, before turning to slip in his strike partner.

King opened up his body and hit a deft, curling effort beyond Pickford. The Black Cats keeper, though, turned quickly and saw the ball bobbling kindly towards him... via the bar and post.

Pickford was similarly grateful to easily scoop up a weak Pugh strike from 20 yards before, at the other end, Simon Francis recovered to block Defoe's shot after the Cherries skipper had initially been bundled off the ball by the England forward.

Defoe did shoot on target on 29 minutes. Pugh skied his clearance from Khazri's left-sided delivery, enabling Dider Ndong to shovel the ball back into Cherries' box.

Sunderland striker Defoe had darted in behind the visiting defence and he met the ball on the volley but only succeeded in directing it towards Boruc, standing tall and gathering safely.

The sides then traded half-chances. King fed Smith for an effort from range that skipped up into the plunging Pickford's midriff, before Defoe drilled wide after sharp build-up play by Pienaar and Borini.

While the home team never looked anything less than a bag of nerves at the back, they were getting the job done... just.

Pugh raced onto Fraser's sharp, forward pass to cut the ball back for Afobe, whose goalbound strike was knocked off course by the scrambling Manquillo.

King had to wait an age for the ball to drop. When the Norwegian did get his shot away, from a slightly awkward angle, it was precise enough to beat Pickford, but not Love, stationed directly behind his goalkeeper and thrashing clear.

Another blocked Afobe effort, shortly before half-time, inadvertently put Cherries in a real spot of bother. Ndong pounced on the loose ball and, spying the ever-alert Defoe dashing into space, lifted a pass forward intended for his striker.

It would have got there as well, were it not for a terrific full-stretch intervention by Francis.

The action was equally stretched after the restart.

Pugh was unable to get sufficient power on his header to trouble Pickford after meeting King's right-sided cross, with the winger then bending an effort past the far post from the left of the box.

Those efforts sandwiched an enthusiastic – but futile – penalty appeal from Fraser, who was sent scurrying into the area by Lewis Cook's slide rule pass down the right before stumbling under a challenge from Manquillo.

Boruc maintained the stalemate by diving to his right to beat away a fierce Borini strike, while Pickford wasn't quite so extended in the act of collecting Fraser's tame, low 20 yarder.

Fraser's 54th-minute free-kick from the right had a bit more devil about it, locating Steve Cook, who couldn't keep his header low enough to drag Pickford back into action.

Homegrown George Honeyman's arrival in place of Pienaar – recently booked for a nasty tackle on King – drew the biggest roar of the afternoon from the home crowd, thus far. If you exclude the cheers that greeted any goals in the kids' match at half-time that is, such is the way of things in these parts right now.

And Honeyman swiftly set about trying to improve his popularity rating further.

Defoe charged forward, shaking off Harry Arter's attempt to chop him down – or take one for the team, as it is termed these days – and evaded Steve Cook before cutting the ball back across for Borini.

The former Liverpool man delayed, seemingly sucking the life from the attack – and his team's fans let him know about it. Honeyman, though, was running intelligently in behind Cherries' backline.

When Borini's pass found him, the young midfielder swiped a shot at the near post that Boruc repelled by dropping sharply to his right.

Pugh headed over after ducking in on Love's blind side to meet Smith's lofted cross. But the noise levels on Wearside were soon being raised again.

The catalyst this time was the backtracking Borini hacking down Lewis Cook. Arter was first on the scene, hurriedly followed by most of the 20 outfield bodies on the pitch.

When the dust settled, referee Stuart Attwell made do with cautioning Borini and Arter.

And Attwell was on centre stage again as the game reached its denouement.

King was convinced he should have had a penalty when Lamine Kone's tug on the striker's shoulder saw him hit the deck. There was nothing doing, though, as was the case seconds later when Francis clipped Khazri's ankles in Cherries' penalty area.

You suspect the official might have given it, but for what had happened immediately beforehand.

Boruc, in terrific form again in the week the club confirmed he will stay next season, gloved away Love's shot through a crowd of bodies as Sunderland pressed for the decisive goal, with Steve Cook then diverting Defoe's cross behind after Kone had flicked on a free-kick pumped forward by Pickford.

Then came the late drama.

The ball had scarcely hit the net before Moyes bore the brunt of the home fans' frustration, 'we want Moysie out' echoing around this cavernous stadium.

All that was a sideshow as far as Cherries were concerned though. They had what they had come for.

Sunderland (4-4-2): Pickford, Love, Kone, O'Shea, Manquillo, Borini, Ndong, Pienaar (Honeyman, 55), Khazri, Anichebe, Defoe.

Unused subs: Djilobodji, Lescott, Embleton, Januzaj, Gooch, Mannone (g/k).

Booked: Pienaar, Borini, Khazri.

Cherries (4-4-2): Boruc, A Smith, Francis, S Cook, Daniels, Fraser, Arter, L Cook, Pugh (Mousset, 82), King, Afobe (Stanislas, 57).

Unused subs: Gradel, B Smith, Mings, Ibe, Allsop (g/k).

Booked: L Cook, Arter.

Referee: Stuart Attwell (Warwickshire).

Attendance: 38,394 (1,127 away fans).