The 20th-seeded Querrey won 6-3, 6-4, 6-4 Sunday. He has made the fourth round at two straight majors. Querrey lost there at Wimbledon to Andy Murray, a possible next opponent. He also advanced to the fourth round of the 2008 U.S. Open.
Querrey had 19 aces and 42 winners.
Story continues below ↓advertisement | your ad hereSpain's Almagro won two titles this year, both on clay.
No. 18 John Isner had a match later Sunday against 12th-seeded Russian Mikhail Youzhny. And No. 19 Mardy Fish plays his fourth-round match Monday against No. 3 Novak Djokovic.
Top seed Rafael Nadal had no problem powering past Gilles Simon 6-4, 6-4, 6-2.
In another match, Feliciano Lopez advanced to the fourth round after Sergiy Stakhovsky retired in the second set because of a right toe infection. The 23rd-seeded Lopez was leading 6-3, 4-0
Other men's winners Sunday included No. 10 David Ferrer, who beat fellow Spaniard Daniel Gimeno-Traver in straight sets, and No. 8 Fernando Verdasco, a four-set winner over 31st-seeded David Nalbandian. It took 39 minutes to compete the first five games of the Verdasco-Nalbandian match.
"I think mentally I was really strong, even like in the first set for (five) games, almost 40 minutes, I was there all the time," Verdasco said. "You know, I felt positive and really good and focused."
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