Harry Maguire and Tyrell Malacia put through their own goal late on as Manchester United squandered a comfortable lead in a 2-2 draw against Sevilla in the first leg of their Europa League quarter-final tie.
Captain Maguire deflected into his own net in the 92nd minute, just eight minutes after Malacia had turned past David de Gea as Sevilla somehow found a way back at Old Trafford in the quarter-final first leg.
A Marcel Sabitzer first-half double appeared to have Erik ten Hag's hosts in complete control, only for the late drama to leave United reeling by full-time.
Jose Luis Mendilibar's side will boast home advantage in a week's time as they eye a seventh Europa League title since the 2006-07 season.
Jadon Sancho fired past Sevilla keeper Bono with less than 30 seconds on the clock, only to be curtailed by a late offside flag.
A smart Bono stop denied Antony soon after, though the goalkeeper could do little two minutes later as Bruno Fernandes found Sabitzer, whose strike deflected into the top-left corner.
Sabitzer added his second just six minutes later after latching onto Anthony Martial's throughball and drilling past Bono.
De Gea kept United's lead intact at the interval after producing an expert save against a Tanguy Nianzou header from Ivan Rakitic's corner.
Antony twice went close after the break, whipping a curling effort wide before seeing a similar attempt smash off Bono's right post.
Christian Eriksen's 62nd-minute introduction after three months out injured came as United seemed set for victory, only for Malacia to offer Sevilla hope when turning Jesus Navas' low cross into his own net.
Sevilla then seized an unlikely comeback in the closing stages as Youssef En-Nesyri's header fortuitously deflected off Maguire and wrongfooted De Gea.
What does it mean? Sevilla record plays Devil in United's mind
United defeated Real Sociedad in the group stages and edged past LaLiga leaders Barcelona in the first knockout round before comfortably dispatching Real Betis in the last 16.
Their impressive run against Spanish sides appeared all but certain to continue until the late drama, as Sevilla maintained their streak of never losing against United, with this their third European meeting.
With that record in the back of United's minds at the Ramon Sanchez-Pizjuan Stadium, Ten Hag will have to find a way past Mendilibar's side, who will be buoyed with confidence following their late fightback.
Fantastic Fernandes withdrawn
Fernandes has 60 goals and 50 assists since his United debut in February 2020, with Lionel Messi (80G, 59A) the only other player in Europe's top-five leagues to hit half-centuries for both those returns in that period.
Yet Ten Hag opted to withdraw the midfielder for Eriksen, a decision that proved costly and United's misery will be compounded as Fernandes will miss the second leg due to his first-half caution.
United gift Sevilla chance
United could have extended their lead multiple times in the second half, boosting hopes of a treble after winning the EFL Cup and reaching the FA Cup semi-finals.
But after United became just the second English side to score two own goals in a single match in a major European competition, after Chelsea against Ten Hag's Ajax in November 2019, Sevilla will fancy their chances.
What's next?
Before the return leg in Spain, United visit Nottingham Forest in the Premier League on Sunday, when Sevilla travel to Valencia in LaLiga.