Manchester City handed the advantage firmly to Liverpool in the Premier League title race as they surrendered the lead in a stunning 2-1 loss away to Newcastle United on Tuesday.
Pep Guardiola's second-placed side looked likely to keep the pressure on Jurgen Klopp's leaders as Sergio Aguero got them off to an ideal start in the Spaniard's 100th league game in charge by scoring the fastest goal of the season just seconds into the action at St James' Park.
But Newcastle staged an unlikely comeback to ease their relegation fears thanks to Salomon Rondon's 66th-minute equaliser, the first goal City had conceded for more than 10 hours, before Matt Ritchie struck the winner from the penalty spot with 10 minutes remaining after Fernandinho's foul on youngster Sean Longstaff.
It means Liverpool, who could have been only a point ahead of their main rivals on their return to action, can extend their lead at the top to an imposing seven points with victory over Leicester at Anfield on Wednesday.
Such a scenario looked unlikely when Aguero continued his amazing scoring record against the Tyneside club with his 15th goal in 13 games against the Magpies, more than any player has scored against an opponent for a single club in the Premier League.
Newcastle manager Rafael Benitez made no apologies for setting out to 'park the bus' against free-scoring opponents, even at home, but the Spaniard's plans to frustrate Guardiola's side were left in tatters when the visitors took the lead with their first attack.
United failed to deal with Raheem Sterling's centre from the right, and although David Silva slipped as he met the cross at the far post, the midfielder did enough to redirect the ball into the path of the lurking Aguero, who found the net for the third successive match with a close-range finish past goalkeeper Martin Dubravka when there were just 24 seconds on the clock.
The Argentina international was denied a second inside opening 20 minutes when he deftly glanced home Kevin De Bruyne quickly-taken free-kick, only for play to be brought back as the midfielder was cautioned for curling in the set-piece before referee Paul Tierney had signalled play could recommence.
Belgium star De Bruyne was fortunate not to earn a second yellow card on the hour when clumsily fouling Ritchie as City's evening began to unravel.
Silva, who posed a constant threat, saw a close-range header cleared off the line by Fabian Schar as City pushed for a decisive second goal, which should have arrived when Sterling failed to make sufficient connection to a Leroy Sane cross shortly after the re-start.
Rondon stuck to his largely thankless task as Newcastle's lone forward, and was rewarded for his efforts with the leveller midway through the second period. City failed to deal with Ritchie's cross, Isaac Hayden heading the ball back into the box to allow Rondon to strike with a firm volley past a stranded Ederson.
Worse was to follow for a City side that had won their previous seven games, as Newcastle sealed a first league victory against the reigning English champions since 2005.
The usually reliable Fernandinho was at fault as the Brazilian fouled Longstaff after being dispossessed in the area by the Newcastle midfielder.
Ritchie kept his composure after lengthy treatment for an injury to Ederson, finding the net despite the Brazilian getting a hand to the Scotland international's spot-kick to seal a memorable night for the hosts.