A penalty from Sven Kums secured Gent's first-ever win in the Champions League, as they defeated a disappointing Valencia 1-0 at Ghelamco Arena.
The Belgian side kept alive their hopes of qualifying for the knockout stages with a well-deserved victory over their Group H rivals.
The result means Valencia missed out on the opportunity to join Zenit, who defeated Lyon 2-0, in going through to the knockout stages.
Gent merited their maiden triumph, and the final margin of victory would have been even greater had they not been so wasteful in front of goal.
Danijel Milicevic saw a looping header from Kenneth Saief's cross hit the right-hand post, strike the back of Valencia goalkeeper Jaume Domenech and then roll along the goal line.
Sloppy in possession and shaky at the back, Valencia failed to even have a shot at goal in the first 45 minutes.
They had to improve as an attacking force once Kums had broken the deadlock from the spot, punishing Barragan for blocking Saief's cross with an outstretched hand.
Yet the surge for an equaliser never really materialised. Coach Nuno summoned Joao Cancelo and Andre Gomes from the bench, yet the substitutes failed to lift the lethargic visitors.
Paco Alcacer's low shot from the left forced Matz Sels into a rare save on what was an otherwise easy night for the Gent goalkeeper.
