defending champion recorded the first "double bagel" in a quarterfinal at the U.S. Open since 1989, when 18-time major title winner Martina Navratilova did it to Manuela Maleeva.
"When you play against Serena," Suarez Navarro said, "you know these things can happen."
Williams won 53 of 71 points and dominated the statistical categories. The first set took all of 19 minutes. The second was slower, lasting 33 minutes, but no less lopsided.
Williams was asked whether she'd describe her performance as close to flawless.
"Of course not," the defending champion said with a laugh. "I played good, though. I played really good. I was just more focused than anything. I like to believe there is room for improvement."
That might be bad news for her opponent in Friday's semifinals, 2011 French Open champion Li Na of China.
Through five matches, Williams has dropped a total of 13 games. Suarez Navarro lost more games than that in her previous match alone, 15, while eliminating No. 8 Angelique Kerber.
That victory, and her seeding, should have demonstrated that Suarez Navarro is quite capable of playing well, too. But not on this evening. Not against Williams, who is 65-4 with eight titles in 2013.
Going back to the start of Wimbledon last year, the 31-year-old American is 96-5 with 13 trophies, including from three of the past five Grand Slam tournaments plus the London Olympics.
"The conditions were so tough, so it definitely was not her best tennis today," Williams said about Suarez Navarro, who was playing in her third career major quarterfinal, and it was on her 25th birthday.
The swirling wind in Arthur Ashe Stadium sure did not appear to bother Williams, who had a 20-3 edge in winners. She made fewer unforced errors, 12-9. She won 23 of 26 points on first serves.
"I've been playing here for, like, 50 years," Williams said with a laugh. "I've kind of gotten used to the conditions. Even though it's difficult to play each year, I'm getting a little bit better with it."