Angelo Ogbonna missed the crucial penalty as a youthful Blackburn dumped West Ham out of the Carabao Cup 10-9 on spot-kicks.
After 19 successful penalties Ogbonna’s effort crashed off the underside of the crossbar to send Championship Rovers through to round four following a 2-2 draw at the London Stadium.
It was a deserved win for a callow Rovers side with an average age of just 22 and a half as boss Jon Dahl Tomasson made 11 changes with more than one eye on Sunday’s Championship derby against promotion rivals Burnley.
They led through an early goal from Jack Vale before Pablo Fornals hauled West Ham level and Michail Antonio put the hosts in front.
But substitute Ben Brereton Diaz, Rovers’ top scorer, sent the match to a shootout and Italian defender Ogbonna was the fall guy.
Hammers boss David Moyes had also made 11 changes, but the hosts were still full of internationals.
Yet Blackburn’s kids had them rattled from the start and Nayef Aguerd was pressured into a backpass which sold Alphonse Areola horribly short.
But the Hammers goalkeeper, who moments before kick-off was named in France’s World Cup squad, was able to block the shot from Dilan Markanday.
However, Areola was beaten in the sixth minute when Vale, 21, collected Tayo Edun’s pass and slotted the ball through the keeper’s legs for his first Rovers goal.
The equaliser arrived seven minutes before half-time when Antonio outmuscled full debutant Clinton Mola, a former Chelsea youngster, down the right and pulled the ball back for Fornals to sweep home.
After the break Antonio attempted to bundle in a Fornals corner at the far post but could only hit the upright.
Tomasson, perhaps starting to fancy his chances, sent on Brereton Diaz and the Chile international immediately fizzed a shot across goal and wide.
Antonio bulldozed his way through once more but was unable to finish and substitute Said Benrahma blazed the rebound over.
Moyes made a further change by sending on Jarrod Bowen and Gianluca Scamacca, and almost immediately West Ham went ahead.
Aguerd lifted the ball into the area, Bowen got a touch and it fell for Antonio to rifle home for his first goal in seven matches.
Yet with three minutes left Rovers came forward again and Brereton Diaz curled a superb shot past Areola to take West Ham to penalty shootout purgatory.