Nordi Mukiele scored a dramatic late winner as Bayer Leverkusen inflicted a first Champions League defeat of the season on Inter Milan.
The result means Xabi Alonso's side leapfrog the Italians, moving second in the table behind Liverpool and into an excellent position to advance to the last 16 automatically as one of the best eight teams.
The 90th-minute intervention from on-loan Paris St-Germain defender Mukiele came as a largely uneventful contest appeared destined to end in a stalemate.
However, Mukiele popped up to blast home from close range after Simone Inzaghi's side had failed to clear a cross from the right.
While Inter fought a rearguard action for much of Tuesday evening they restricted the hosts to a handful of shots on target and will be disappointed by the manner in which they conceded their first goal in the competition this term.
Leverkusen were largely frustrated until the final moments, though the complexion of the match may have altered significantly had the hosts taken either one of two excellent opportunities at the start of each half.
The German champions were unfortunate to see Nathan Tella's effort rebound off the crossbar after Jeremie Frimpong had pulled the ball back into his path with just under three minutes on the clock.
And Netherlands international Frimpong then flicked an effort wide of the far post with the outside of his boot after collecting Florian Wirtz's incisive pass after the interval.
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