Stade Francais fought back from a 14-0 deficit to claim victory over Worcester in their opening Amlin Challenge Cup Pool One game at Sixways.
Tries from Chris Pennell and Marcel Garvey, converted by Joe Carlisle, saw Worcester race clear after 12 minutes.
But Felipe Contepomi kicked 18 points and freed Paul Sackey, who powered over in the corner, as the visitors rallied.
Worcester's failure to score after their fine early start meant they did not earn a losing bonus point.
Worcester: Pennell; Garvey, Grove, Rasmussen, Arscott; Carlisle, Perry; Mullan, Lutui, Tomaszczyk, Percival, Gillies, Best, Kvesic, C Jones.
Replacements: Classens for Garvey (74), Goode for Rasmussen (60), Frost for Perry (74), Porter for Mullan (70), Shervington for Lutui (60), Taumoepeau for Tomaszczyk (54), Balding for Gillies (70), Betty for Best (60).
Stade Francais: Williams; Sackey, Contepomi, Tiesi, Camara; Warwick, Fillol; Roncero, de Malmanche, S. Wright, Palmer, Pape, Tomiki, Lyons, Parisse.
Replacements: Fainifo for Tiesi (62), Sempere for de Malmanche (57), Mostert for Palmer (71), Milloud for Tomiki (29).
Not Used: Slimani, Burban, Kelleher, Plisson.
Sin Bin: Roncero (26).