Giant American John Isner battled back from a set down against Colombian qualifier Santiago Giraldo to win his opening match 4-6 7-5 7-5 at the typhoon-hit Shanghai Masters on Monday.

The 14th-seed dodged heavy rain and swirling winds by playing under the closed roof at the Qizhong tennis centre, but struggled to impose his heavy-serving game on the 83rd-ranked Colombian in a performance strewn with errors.

The 2.08m Isner – America’s top player – lost the first set but dug deep to win the second set 7-5, levelling the match on his seventh set point.

Isner, who fired down 29 aces but made 32 unforced errors, broke Giraldo in the 12th game of the decider to seal victory.

Earlier, Spain’s Marcel Granollers was a 6-4 6-4 winner over out-of-sorts Serbian Janko Tipsarevic, who required attention from the physio for an apparent left ankle problem.

Granollers, 36th in the world, broke the bespectacled Tipsarevic, ranked 12 places higher, early in both sets, which proved decisive.

Roger Federer, seeded fifth in the singles, is on Monday teaming up in the doubles competition with China’s Zhang Ze, ranked 271st.

The Swiss 17-time Grand Slam winner, who has slipped to seventh in the singles rankings, is in danger of missing out on next month’s end-of-season ATP World Tour Finals, currently held in London, for the first time since 2001.

He faces a potential quarter-final meeting with defending champion and top seed Novak Djokovic, who has dropped one place to world number two behind Rafael Nadal, despite beating the Spaniard in the China Open final at the weekend.

The top eight seeds in Shanghai all have a bye through to the second round.

Typhoon Fitow slammed into China’s east coast on Monday, packing winds of more than 200km/h and bringing drenching rains, forcing changes to the scheduling of the tournament.