Andy Roddick reached the third round of the Shanghai Masters on Tuesday, coming out on top with a 7-6 (7/3), 7-5 win against Bulgaria's Grigor Dimitrov.
The American 10th seed won a first set tie-break and sealed victory after clinching a topsy-turvy second set that contained five breaks of serve.
After Dimitrov broke Roddick in the ninth game of the second set to lead 5-4, the American smashed his bag repeatedly in frustration but he immediately broke back to level at 5-5.
Earlier, Germany's Florian Mayer, the 15th seed, beat former world number three David Nalbandian 6-3, 6-4 to reach the third round and seventh seed Nicolas Almagro defeated Spanish compatriot Tommy Robredo 7-5, 6-3.
In other first round clashes, Serbian ninth seed Janko Tipsarevic crashed out to Feliciano Lopez of Spain 6-7 (2-7), 6-7 (3-7), dealing a heavy blow to his hopes of reaching the ATP World Tour Finals.
Tipsarevic won his first ATP title earlier this month at the Malaysian Open but lost in the first round of last week's Japan Open.
Austrian 14th seed Jurgen Melzer, who defeated Rafael Nadal to reach the quarter-finals in Shanghai last year, beat Croatia's Ivan Ljubicic 6-4, 6-2, and Alexandr Dolgopolov, seeded 12, beat Lukasz Kubot of Poland 6-4, 7-6 (8/6).
Japan's Kei Nishikori overcame a disastrous start against Robin Haase to defeat the Dutchman 0-6, 7-5, 7-6 (7/5).