Hamburg - Veteran Tommy Haas rallied to upset defending champion Gilles Simon 4-6, 6-3, 6-4 on Wednesday for a place in the quarterfinals of the German Tennis Championships.
Haas beat Roger Federer for the title in Halle, Germany, in June and is looking to become the first home player to win the tournament since Michael Stich in 1993.
Haas will next meet another German, Florian Mayer, who routed Robin Haase 6-2, 6-1.
Fourth-seeded Marin Cilic stayed on course for a second title in two weeks by dismissing Federico Delbonis 6-3, 6-2.
Albert Ramos beat Lukas Rosol 7-6 (10/8), 4-6, 6-3.