Florida - Third-seeded Sam Querrey of the US double-faulted on the last two points of the deciding 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.
"I played a sloppy game at 4-1, and then at 5-4 I played some tentative shots and the double-fault killed me and then it's a 50-50 match after that." Querrey said. "It was just one of those days, one of those matches."
The 109th-ranked Gulbis won his first of two career titles at Delray Beach in 2010.
Gulbis smashed his racket when he lost his serve in the first game of the third set, which delivered a warning from the umpire.
Then in the fifth game of the third set, Gulbis took a point penalty after cursing.
"At that moment you don't care so much," Gulbis said of trailing two service breaks in the third set. "If I didn't get that first service break back then, it would be over real fast."
Second-seeded Tommy Haas of Germany moved into the quarterfinals with a 6-4, 6-1 win over Denis Istomin of Uzbekistan.
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.
"It's a little different with the cool weather and no wind today so it was very pleasant to play," Haas said. "I had a lot of chances early on that I didn't take and frustrated me, but at 4-5 I broke him to win the first set and that mentally disturbed him a little bit."
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, and Ivan Dodig of Croatia beat Evgeny Donskoy of Russia 6-3, 7-5.