Eintracht Frankfurt produced a stunning performance as they reached the Europa League semi-finals with a 3-2 second-leg victory over Barcelona at Camp Nou on Thursday.
The two sides played out a 1-1 draw in Germany last week, and any thoughts Xavi's men had of brushing aside their opponents on home turf were dispelled in the fourth minute when Filip Kostic scored from the penalty spot.
Rafael Borre and Kostic added further goals to give the scoreline a scarcely believable look, before a fine Sergio Busquets strike and Memphis Depay penalty reduced the deficit in stoppage time.
But Frankfurt had done enough for a famous 4-3 aggregate win and Oliver Glasner's men will now face West Ham in the last four after they overcame Lyon.
Barca started dismally and fell behind in the fourth minute when Kostic slammed home from the spot after Eric Garcia had hauled down Jesper Lindstrom in the area.
They went 2-0 down in the 36th minute, though, courtesy of a stunning 25-yard strike from Borre that flashed past Marc-Andre Ter Stegen and into the roof of the net.
Ansgar Knauff fizzed a strike narrowly over Ter Stegen's crossbar soon after as Frankfurt threatened to put the tie beyond Barca's reach before the interval.
Frankfurt then sent their fans into dreamland when Kostic drilled across Ter Stegen for his second of the game in the 67th minute.
Busquets thundered home from outside the penalty area in stoppage time moments after having an effort ruled out by VAR for offside, before Depay scored from the spot with almost the last kick of the game after Evan Ndicka had clattered into Luuk de Jong.
What does it mean? Barca's unbeaten run comes to a crashing halt
Few expected Barca's 15-game unbeaten streak to come to an end against a team languishing ninth in the Bundesliga, but Frankfurt were excellent value for their win.
Glasner's side, who had 15 shots to Barca's 10, are now unbeaten in their last 10 games against Spanish sides in European competition (W6 D4), including the last five away from home (W4 D1).
Kostic's game to remember
Kostic started and ended the scoring for Frankfurt, while he also played the key pass before Borre's glorious strike. That made him the first player to score and assist in a single European game against Barcelona at Camp Nou since Juninho Pernambucano for Lyon in March 2009 in the Champions League.
Barca's spot-kick woes continue
Garcia's early penalty concession was Barca's fourth in their last two games – as many as in their previous 55 matches in all competitions. Indeed, Kostic's penalty was the earliest conceded by the Catalan giants in all competitions since the 2004-05 season.
Barca will need to lift themselves when they host Cadiz in LaLiga on Monday, while a buoyant Frankfurt visit Union Berlin in the Bundesliga a day earlier.