SEAD KOLASINAC revealed he could not sleep for three nights after losing to Tottenham.
The ex-Arsenal full-back is now playing for Marseille in France following his transfer last year.
And while his former Gunners team-mates slipped into the Europa League, Kolasinac secured Champions League qualification for this season.
The Ligue 1 went into the final game of a tight Group D at home to Spurs knowing a win would send them through to the knockout stages.
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Chancel Mbemba put Marseille in front just before half-time before Clement Lenglet equalised nine minutes into the second half.
And sub Kolasinac, 29, had a glorious chance to win it - but fluffed his lines and somehow headed wide from close range.
To make matters worse, Marseille were unaware a draw would have at least dropped them into the Europa League.
But in the 95th minute, Pierre-Emile Hojbjerg struck with the final kick of the game to put Spurs top of the group - and sink Marseille to bottom, ending their European journey in devastating fashion.
And Kolasinac was particularly impacted by his own role in the defeat.
As reported by L'Equipe, club president Pablo Longoria revealed the Bosnian told him at the training ground: "I haven’t been able to sleep for three nights because of it."
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Kolasinac, though, has responded brilliantly and is a key man in Igor Tudor's team.
The former Arsenal man - who made 118 appearances across five seasons with the North Londoners - scored the winner against Monaco before the World Cup and has helped Les Phoceens to second behind PSG in the league.
And his popularity and impressive form has seen contract talks open over an extension beyond this summer until 2025.
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