DELRAY BEACH, Fla. — Third-seeded Sam Querrey of the U.S. double-faulted on the last two points of the third-set tiebreaker to lose to qualifier Ernests Gulbis of Latvia 6-4, 4-6, 7-6 (4) at the Delray Beach International Championships on Thursday.
Querrey double-faulted eight times in the match. Querrey, who led 4-0 in the third set, double-faulted at 30-40 when serving for the match at 5-4 in the third set.
Also Thursday, defending champion and sixth-seeded Kevin Anderson of South Africa defeated Yen-Hsun Lu of Taipei 6-4, 3-6, 6-3. Second-seeded Tommy Haas of Germany, who won the Delray trophy in 2006, scored a 6-4, 6-1 win over Denis Istomin of Uzbekistan. Top-seeded John Isner of the U.S. closed out the day with a 7-6 (2), 6-2 win over Go Soeda of Japan.
The 109th-ranked Gulbis won his first of two career titles at Delray Beach in 2010. He smashed his racket when he lost his serve in the first game of the third set Thursday. That delivered a warning from the umpire.
Then in the fifth game of the third set, Gulbis took a point penalty after cursing.
The 34-year-old Haas finished last season ranked 21st and was the oldest player in the world's top 50 players.
Haas, who reached the San Jose final earlier this month, never faced a break point against serve in the 67-minute match against the 42nd-ranked Istomin.
Qualifier Daniel Munoz-De La Nava of Spain upset eighth-seeded Xavier Malisse, a former two-time Delray champion, 7-6 (3), 3-6, 6-3. In other matches, Ricardas Berankis of Lithuania defeated American wild card Jack Sock 3-6, 6-4, 6-1. Eduoard Roger-Vasselin of France beat Ivo Karlovic of Croatia 6-4, 7-5. Ivan Dodig of Croatia beat Evgeny Donskoy of Russia 6-3, 7-5.
At Acapulco, Mexico, Rafael Nadal beat Leonardo Mayer in straight sets to advance to the semifinals of the Mexican Open, setting up a meeting with Spanish compatriot Nicolas Almagro.
The second-seeded Nadal won 6-1, 7-5 in 1 hour, 41 minutes as the former top-ranked player continues his comeback from a long-term knee injury and builds toward the French Open.
Third-seeded Almagro also had a straight-set win, defeating Horacio Zeballos 6-3, 6-4.
Top-seeded David Ferrer remained on track for a fourth-straight Mexican Open title by beating Paolo Lorenzi 6-3, 6-1, notching his 18th consecutive win in this tournament.
Ferrer's semifinal opponent will be Italy's Fabio Fognini, who beat Santiago Giraldo 7-5, 6-4.
Brazil Tennis Cup
At Florianopolis, Brazil, Venus Williams beat fifth-seeded Magdalena Rybarikova of Slovakia 6-4, 6-0 to reach the semifinals of the Brazil Tennis Cup.
The top-seeded American broke Rybarikova's serve at 5-4 to win the first set and quickly took control of the second to clinch the victory in 1 hour, 25 minutes at the hard court tournament in southern Brazil.
The 20th-ranked Williams is playing in her first tournament since losing to Maria Sharapova in the third round of the Australian Open in January.
At Dubai, United Arab Emirates, Australian Open champion Novak Djokovic remained unbeaten this year by routing Andreas Seppi of Italy 6-0, 6-3 as the top four seeds powered into the semifinals of the Dubai Championships.
Defending champion Roger Federer defeated Nikolay Davydenko 6-2, 6-2.
Djokovic will play fourth-seeded Juan Martin del Potro, who returned to the semifinals by beating German qualifier Daniel Brands 6-4, 6-2. Federer will face third-seeded Tomas Berdych, who defeated Russian wild card Dmitry Tursunov for the second time in five days, 6-3, 6-2.