WASHINGTON — Vancouver's Vasek Pospisil fell 4-6, 6-7 (6) to American John Isner in the third round of the Citi Open on Thursday.
It was the final match of the day and didn't finish until 1:30 a.m. Friday, thanks in part to a rain delay of nearly an hour after the third game. Pospisil was last year's Citi Open runner-up.
With the win, Isner advances to the quarter-finals against 86th-ranked Ricardas Berankis, who knocked off top-seeded Andy Murray on Wednesday. Berankis was a 7-5, 6-4 winner against Teymuraz Gabashvili on Thursday.
Earlier in the day, Sam Querrey gave U.S. Open champion Marin Cilic all he could handle in the first set — until the tiebreaker. In the second set, too — until the tiebreaker.
Getting his hard-court game in gear a few weeks before defending his first Grand Slam title, Cilic edged the 13th-seeded Querrey 7-6 (2), 7-6 (3).
"Pretty comfortable tiebreakers," the third-seeded Cilic said, "but if one or two things would be a bit different, it could have been very, very tight."
How close was it? Take away the tiebreakers, and Querrey won more total points, 74-67. The American also compiled more winners, 32-25. And he even served for the second set while up a break at 5-3, but got broken there.
"A little bummed right now. I felt like I didn't necessarily outplay him, but I was right there," Querrey said. "In that first set, I felt like I had all the chances. But the tiebreaker got away from me a little bit. The second set was similar. I needed to tighten things up a little bit when I was serving for the set."
Down 1-0 in the first tiebreaker, Querrey put two first serves in, but lost both points by missing forehands, one into the net, the other wide.
"Right away, I was down 3-0 ... and against a guy like Marin, who's got a great serve himself and is so solid, you feel like you're a long way from the first set at that point," Querrey said. "So it kind of sucks the wind out of you."
With Cilic up 2-1 in the second tiebreaker, he smacked a running, down-the-line forehand winner and raised his left fist.
"That pretty much decided the match," Cilic said.
The Croatian is the first reigning U.S. Open champion to enter Washington's hard-court tournament since Andre Agassi in 2000.
Next for Cilic is matchup with 18-year-old Alexander Zverev of Germany, the youngest quarterfinalist in the nation's capital since Andy Roddick was 17 in 2000. Zverev got past 2012 Citi Open champion Alexandr Dolgopolov 2-6, 6-2, 6-4.
The man Cilic defeated for the title at Flushing Meadows last year, Kei Nishikori, played nearly mistake-free tennis to move into his 11th ATP quarter-final of the season by beating 16th-seeded Leonardo Mayer of Argentina 6-4, 6-4.
The second-seeded Nishikori made only seven unforced errors, half as many winners as he produced in the 1 1/2-hour victory.
Nishikori meets Sam Groth for a berth in the semifinals. Groth delivered 20 aces in a 6-3, 6-4 victory over seventh-seeded Feliciano Lopez.
"I'm going to have to play my game style. Nothing changes too much for me," Groth said, looking ahead to facing Nishikori. "I've got to hold serve and I've got to build pressure around that and I've got to make him feel uncomfortable. I'm going to attack the net. I'm going to be aggressive and I'm going to do what I do."
Jack Sock and Steve Johnson set up an all-American quarter-final by eliminating seeded opponents. Sock came back to beat No. 4 Richard Gasquet of France 6-7 (4), 7-6 (5), 6-4, while Johnson got past No. 6 Grigor Dimitrov of Bulgaria 6-3, 1-6, 6-3.
Women's winners included top-seeded Ekaterina Makarova, Anastasia Pavlyuchenkova and Christina McHale.
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Howard Fendrich, The Associated Press