Ernest Gulbis almost proved to be a thorn in Jo-Wilfred Tsonga's title defense here at the PTT Thailand Open as he took the Frenchman the distance in a 2 hour 12 minute three set tie breaker encounter. Tsonga, however, won an extra point to win the match 6-7(3) 7-6(4) 7-6(2).

In all, there were 43 aces fired in the match, 20 flying from Tsonga's racquet. As the score suggests, both the players acted miser on their serves fighting for every point.

After eradicating the Latvian, Tsonga will next face Swiss qualifier Marco Chiudinelli, who ended Marat Safin’s campaign with a 6-3 7-6(4) victory over the Russian.

World No. 10 Gilles Simon made a strong start to his debut campaign in Bangkok by cruising past American Kevin Kim 6-2 6-2 in just 61 minutes to enter his sixth ATP Tour quarter final of the season. He will be up against Russian Evgeny Korolev, who dismissed American Robby Ginepri 6-1 6-1.

American eighth seed John Isner defeated German Mischa Zverev 7-6(5) 6-4 in 83 minutes to book a place in his sixth ATP World Tour quarter-final of the season.

German Andreas Beck ended American lucky loser Donald Young's campaighn with a 6-1 6-7(3) 6-4 victory to set up a quarter-final meeting with sixth seed Jurgen Melzer.