Shanghai: Big-serving Jo-Wilfried Tsonga was sent crashing out of the Shanghai Masters on Wednesday by Japan's Kei Nishikori but untroubled top seed Rafael Nadal eased through to the third round.

Tsonga, the fourth seed, who lost 7-6 (7/1), 4-6, 4-6, appeared to be on his way to a straightforward victory when he stepped up the intensity to seal the first-set tie-break with the loss of just one point.

But world number 47 Nishikori, who needed courtside treatment on his back, broke twice in the second set, levelling the second-round match when the Frenchman netted with a forehand.

Nishikori, who has a poor record against top-10 players, produced two more breaks in the deciding set, taking advantage of an error-strewn performance by Tsonga and sealing the win on his third match point.

The defeat puts a serious dent in the Frenchman's bid to reach next month's ATP World Tour Finals. He came into the Shanghai Masters in eighth place in the race to reach the showpiece, featuring the top eight players of the year.

"Of course I'm disappointed because I lost. But today I had a good opponent," said Tsonga.

He praised Nishikori, saying: "He returned unbelievable. I think nobody breaks me many times like this." Tsonga struck 11 aces in the match but was broken four times in total and made 45 unforced errors.

Referring to his chances of reaching the year-end ATP tournament in London, he said: "At the moment I'm confident. I will take some rest and then I will come back to qualify."

In his first match of the tournament after a first-round bye given to the top eight seeds, world number two Nadal, bidding for his 20th Masters title, beat fellow Spaniard Guillermo Garcia-Lopez 6-3, 6-2.

Speaking after his win, Nadal, who lost to Garcia-Lopez in Bangkok last year, said: "It was a little bit in my mind today in the break points, that's the truth... I have a comfortable victory in two sets."

But he spoke of his unhappiness about players' health being put at risk by having to adapt to different balls from week to week, calling for action to address the situation.

"It's unbelievable how the conditions can change from Tokyo to here. The ball is completely different. Something must change because is too dangerous for the shoulders. For us it is a big change," said Nadal.

Nadal's comments echo those of Andy Murray, who Tuesday called for more consistency in the balls used.

Second seed and defending champion Murray had a walkover into the third round after Dmitry Tursunov of Russia withdrew from their match with a right thigh injury.

Spain's third seed David Ferrer came out on top 7-5, 7-6 (9/7) in his second-round clash with Canada's Milos Raonic, and Czech player Tomas Berdych beat compatriot Radek Stepanek 6-4, 6-3.

Earlier, Juan Carlos Ferrero came from a set down in an all-Spanish tie to oust 16th seed Fernando Verdasco 4-6, 6-3, 6-2, breaking six times during a match lasting a little over two hours.

There was also a win for 12th seed Alexandr Dolgopolov of Ukraine, who overcame Spain's Albert Ramos 5-7, 6-3, 6-2.

Austria's 14th seed Jurgen Melzer lost in three sets to Colombia's Santiago Giraldo while Australia's Matthew Ebden beat America's Ryan Harrison in straight sets.

In the late match, Spain's Feliciano Lopez beat Alex Bogomolov Jr of the United States 7-6 (7/4), 3-6, 6-3.

World number one Novak Djokovic, Nadal, Roger Federer and Murray have already qualified for the year-ending ATP finals.