SHANGHAI (AP) John Isner served 29 aces and rallied to beat Colombian qualifier Santiago Giraldo 4-6, 7-5, 7-5 on Monday in the first round of the Shanghai Masters.
The 14th-seeded American fought off three break points at 5-5 in the third set, then broke Giraldo for the second time to close out the match.
"I started off a little slow in the first set," Isner said. "I told myself the only thing I could do was keep fighting. I felt like I was serving well, so just try to hold serve as best as I could. That's what I did."
Isner could meet Rafael Nadal in the third round.
Nadal, seeded second in Shanghai, supplanted Novak Djokovic as the top-ranked player on Monday, despite losing to the Serb in the final of the China Open in Beijing a day earlier.