Milan Biševac headed the only goal of the game on 64 minutes as Olympique Lyonnais got the better of Grasshopper Club in the first leg of their UEFA Champions League third qualifying round tie.
The Serbian defender rose to plant a firm header inside goalkeeper Roman Bürki's left-hand post after Clément Grenier had teed him up with a free-kick swept in from the touchline, but Michael Skibbe's Grasshoppers will feel there is plenty of life left in their challenge after hitting the post twice in the first half at the Stade de Gerland.
The Swiss side could easily have been 2-0 up inside 30 minutes but for the intervention of the woodwork; an excellent shot from Michael Lang rattled the frame of Anthony Lopes's goal on 16 minutes, and Grasshoppers were left to curse their luck again nine minutes later when midfielder Shkelzen Gashi found the post again with a header from a corner.
Rémi Garde's side rode their luck but were building up a head of steam by the interval. Bürki was kept busy, saving from Alexandre Lacazette's header on 36 minutes before making an important intervention to fend away a Grenier free-kick just before the break. However, he could not get a touch to Biševac's excellent header, though the game remains delicately balanced ahead of the return fixture in Switzerland.