Vienna - German top seed and world number five Alexander Zverev crashed out of the Vienna Open on Friday, losing to France's 15th-ranked Jo-Wilfried Tsonga 7-6 (8/6), 6-2.
Tsonga, who marked his return to the tour last weekend with the Antwerp title after a four-week injury absence, will next face German veteran Philipp Kohlschreiber for a semi-final spot.
Kohlschreiber downed Argentina's Diego Schwartzman 7-5, 7-6 (8/6) in his quarter-final.
Results from the ATP tournament in Vienna on Friday (x denotes seeding):
Jo-Wilfried Tsonga (FRA x8) bt Alexander Zverev (GER x1) 7-6 (8/6), 6-2
Philipp Kohlschreiber (GER) bt Diego Schwartzman (ARG) 7-5, 7-6 (8/6)
Kyle Edmund (GBR) bt Jan-Lennard Struff (GER) 6-2, 7-5
Lucas Pouille (FRA) bt Richard Gasquet (FRA) 7-6 (7/5), 6-1