Tomas Berdych became the third seeded player to fall in the first round of the China Open in Beijing.
The Czech second seed served four double faults and hit 32 unforced errors as he crashed out of the competition in a straight-sets 6-4 6-4 defeat to Uruguay's Pablo Cuevas.
The world number five Berdych told atpworldtour.com: "It's always a difficult part of the year. We have to travel a lot.
"The conditions are always very different, very difficult, week by week here in China. It's not easy to adjust. It's the same for all of us just ahead of the last and big tournament."
Croatia's Ivo Karlovic had no problems with his serving, though, as he smashed down 19 aces on his way to a 7-5 7-6 (7/1) victory over Guillermo Garcia-Lopez of Spain.
In the second round, third seed Rafael Nadal safely secured a quarter-final berth with a hard-fought 7-6 (7/3) 6-4 win against Vasek Pospisil, and he will now take on the Canadian's doubles partner Jack Sock.
American Sock cruised through his second-round match against Austria's Andreas Haider-Maurer, winning 78 per cent of his service points in the 6-3 6-1 victory.
Fourth seed David Ferrer overcame Czech Lukas Rosol with a 7-6 (7/5) 6-2 success and will face wildcard Lu Yen-hsun in the quarter-finals.
Chinese Taipei's Lu converted six of nine break points en route to defeating world number 24 Victor Troicki of Serbia 6-4 7-5.
In the second round of the women's competition, fifth seed Garbine Muguruza brushed aside American qualifier Irina Falconi 6-2 6-1 to advance.
In the third round, Sara Errani battled back from a set down to overcome Germany's 13th-seed Andrea Petkovic 3-6 6-3 6-2 to go through, and she will next take on 12th-seed Timea Bacsinszky.
Switzerland's Bacsinszky edged a topsy-turvy match, which had 11 breaks in total, with seventh-seed Carla Suarez-Navarro of Spain, winning 6-4 4-6 7-5 to progress.
German Angelique Kerber broke eighth seed Caroline Wozniacki seven times to ease into the last eight with a 6-2 6-3 triumph over the Dane.
Fourth seed Agnieszka Radwanska will go through to the last eight after American Madison Keys retired injured with the Pole winning the match 6-3.
Britain's Dominic Inglot and Swedish partner Robert Lindstedt were beaten 4-6 7-6 (7-4) 10-7 in the doubles competition by second seeds Marcin Matkowski of Poland and Serbian Nenad Zimonjic.
Source: PA
