Back on tour after 10 months, Melzer upsets top-seeded Thiem

KITZBUEHEL, Austria (AP) - Playing his first tournament in 10 months, Jurgen Melzer upset fellow Austrian and top-seeded Dominic Thiem 6-3, 7-5 to reach the quarterfinals of the Generali Open on Wednesday.

Thiem's defeat came only hours after defending champion Philipp Kohlschreiber and third-seeded Marcel Granollers also lost in straight sets in the second round of the clay-court event.

Prior to this week, Melzer hadn't played on the tour since undergoing shoulder surgery following last year's U.S. Open. The 35-year-old Austrian held serve throughout and broke the ninth-ranked Thiem once in each set.

"As an athlete you always believe there is a chance," said the formerly eighth-ranked Melzer, who has dropped to No. 421. "Today there was a very small chance but I took it."

Thiem, who pulled out of Hamburg last week due to illness, praised Melzer for "a super performance."

"He was just too good. And I made way too many mistakes," said Thiem, who has won four tournaments this season.

Melzer next plays his younger brother Gerald, who beat Daniel Gimeno-Traver of Spain 6-3, 6-1. It's the first time the Melzer brothers play each other on ATP level.

Earlier, Kohlschreiber, who was seeded second, was upset by the 104th-ranked Karen Khachanov of Russia 6-4, 6-4. The German quickly went 4-0 down and dropped his serve five times in total.

"I am surprised I beat the defending champion. For me it's one of the biggest wins," said Khachanov, who plays Dusan Lajovic in the quarterfinals. The sixth-seeded Serb defeated Mischa Zverev of Germany 6-4, 6-4.

Granollers, who won the event three years ago, was beaten by Adam Pavlasek of the Czech Republic 6-2, 6-4. Pavlasek next takes on Nikoloz Basilashvili of Georgia, who beat Igor Sijsling of the Netherlands 6-4, 4-6, 6-2.

Also, fourth-seeded Paolo Lorenzi of Italy and eighth-seeded Jan-Lennard Struff of Germany advanced to the quarterfinals.