Manchester United handed local rivals Manchester City the 2017-18 Premier League title after succumbing to a shock 1-0 defeat against West Bromwich Albion at Old Trafford that keeps the Baggies' slim survival hopes alive.
Jay Rodriguez was the unlikely man to the seal the championship for City with his 74th-minute goal at Old Trafford.
The match had looked on course to end in a stalmate, with top-drawer saves from David De Gea and Ben Foster the highlights before Rodriguez's goal from a corner handed a third Premier League crown to City.
The result leaves second-placed United just one point above Liverpool, although Jose Mourinho's side do have a game in hand.
West Brom now move to within nine points of safety, although they must face Liverpool, Tottenham and fellow relegation battlers Crystal Palace in their final four matches of the campaign.
Jose Mourinho's men should have had a first-half penalty after Craig Dawson caught Ander Herrera, but complacency seeped in and the Baggies showed fight under caretaker boss Darren Moore that has been sorely lacking this season.
Ultimately, Rodriguez was the hero for West Brom -- and City.
Just days after the Football Association announced a charge of racially abusing Brighton's Gaetan Bong had been found "not proven," the forward netted to secure a victory which sends shockwaves around the league.
"Manchester City, we won it for you" chanted the West Brom fans at the end of a match greeted by jeers by the home faithful.
While still nine points from safety, it was an amazing end to a match that had started with Livermore showing composure that belied his role as a midfield enforcer as he cut away from Victor Lindelof to be denied by De Gea.
Salomon Rondon saw a close-range header comfortably denied in the Baggies' other noteworthy first-half attempt, although United were taking their time to break down the brittle visitors.
Foster comfortably stopped a hopeful long-range Paul Pogba attempt and raced off his line to thwart former West Brom teammate Romelu Lukaku, but the ex-United goalkeeper was fortunate not to be facing a penalty in the 18th minute.
Lukaku cut back for Herrera and Dawson caught the midfielder, yet referee Paul Tierney did not award the spot-kick.
The official was on hand 10 minutes later to book Pogba after attempting to throw the ball in, only exacerbating the testimonial feel at Old Trafford.
There were a few United half-chances before half-time, while a Dawson header back across goal from a corner was begging to be turned in by West Brom.
Jesse Lingard came on for Herrera at half-time and immediately saw an attempt blocked - but the hosts continued to struggle for coherence.
Rondon had a header saved and Juan Mata flashed wide, before Mourinho turned to Anthony Martial in place of Pogba as heavy rain fell.
Foster impressively denied Lukaku when meeting a clipped Matic cross and Lingard had an attempted deflected wide as a goal looked inevitable.
But few would have predicted it coming against De Gea.
Chris Brunt's corner to the far post was headed back towards his own goal by Nemanja Matic under pressure from Dawson, with Rodriguez stealing in to head in from close range in the 73rd minute.
James McLean fired across face of goal and United failed to muster a leveller. Chris Smalling had an attempt as the clock wound down and the full-time whistle saw City crowned champions.