Top seed David Ferrer was dumped out of the China Open by world number 92 Dudi Sela Thursday as home favourite Zheng Jie cruised through to the quarter-finals.
Ferrer, playing his first match of the tournament, lost 6-3, 6-3 in 70 minutes to the Israeli.
Sela established an early advantage against the world number five, part of a strong Spanish contingent here, breaking him early in the first set.
Then he broke Ferrer to love in the fifth game of the second set, taking advantage of a string of unforced errors, and went on to seal the match.
Meanwhile, Zheng followed up her first round victory over 10th-ranked Agnieszka Radwanska with a 6-1, 6-2 win over Japanese veteran Ai Sugiyama.
Zheng, who reached the Wimbledon semi-finals this year and took an Olympic doubles bronze, is the only Chinese player left in the men's or women's draws.
The best performance by a Chinese player at this tournament was by Peng Shuai, who reached the semi-final of the 2006 China Open but was one of the first-round losers on Tuesday, along with the host nation's top player Li Na.
Second seed Andy Roddick was due to open his campaign against compatriot Brendan Evans.
Serbia's Ana Ivanovic, seeded second in the 600,000-dollar women's draw, was looking to turn around a poor spell of form that included a second round exit at the US Open.
Ivanovic, who won the French Open this year, is currently ranked fourth in the world and along with fellow Serb Jelena Jankovic, is targeting the top spot in the world game, currently held by Serena Williams.
In the men's 524,000-dollar tournament, Roddick will face stiff competition from 2007 champion and Olympic silver medallist Fernando Gonzalez, who starts his defence Thursday evening.