Grasshopper Club face a tough trip to France next week after suffering a 2-0 home defeat by LOSC Lille in the first leg of their third qualifying round tie.
Sébastien Corchia put the visitors in front in Zurich and Ryan Mendes clinched the victory just four minutes after the break. LOSC will now be confident of doing enough in next week's return to book a place in the play-off draw on 8 August.
Israeli Under-21 international Munas Dabbur had his shot blocked on the line as Grasshoppers threatened early. However, it was the French side who took the lead when former France U21 right-back Corchia volleyed in after fine work by Mendes. René Girard's team took control of the tie and Mendes sealed the victory following a cross by Corchia.