Nice - Nikolay Davydenko beat top-seed John Isner 6-4, 7-6 (7/4) to reach the Nice Open semi-finals, while second-seeded Gilles Simon and No 3 Nicolas Almagro also won on Thursday.
Although Isner hit 13 aces, the American couldn't break Davydenko's serve. The Russian saved three break points and broke Isner once in the first set.
Davydenko, once ranked third in the world, next plays either Brian Baker of the United States - ranked 216th - or Mikhail Kukushkin of Kazakhstan. They were playing later on Thursday.
Simon, who grew up in Nice, did not face a single break pointin a comfortable 7-5, 6-0 win against Brazilian Thomaz Bellucci.
He will play Almagro for a place in Saturday's final, after the Spaniard beat Belgium's Steve Darcis 6-4, 6-4.
Results from the fourth day of the ATP tournament on Thursday (x denotes seeding):
Nikolay Davydenko (RUS) bt John Isner (USA x1) 6-4, 7-6 (7/4)
Brian Baker (USA) bt Mikhail Kukushkin (KAZ) 4-6, 6-3, 7-6 (7/4)
Nicolas Almagro (ESP x3) bt Steve Darcis (BEL) 6-4, 6-4
Gilles Simon (FRA x2) bt Thomaz Belluci (BRA) 7-5, 6-0