Poor defending cost the hosts dearly. Sloppy marking allowed Dieumerci Mbokani to beat for the first Standard goal, and Nigerian Joseph Yobo gifted Standard the second goal with an own goal.
Meanwhile, their U.S. teammate, Carlos Bocanegra, scored the winning goal on a header for Rennes in its 2-1 home win over Twente.
Neven Subotic's first European match ended in defeat when Borussia Dortmund fell at home to Udinese, 2-0.
Brad Friedel was in goal for Aston Villa's 3-1 win at Litex Lovech.