NEW YORK — From an ace on the first point to a stinging return on the last, Serena Williams was close to perfect in the US Open quarterfinals.
The score said it all: 6-0, 6-0.
Yes, Williams is looking better and better with each match at the year’s last Grand Slam tournament. With two more wins — no matter the exact scores — she'll earn a fifth title at Flushing Meadows and 17th major championship overall.
The No. 1-ranked and No. 1-seeded Williams shut out 18th-seeded Carla Suarez Navarro of Spain, the first ‘‘double bagel’’ in a quarterfinal at Flushing Meadows since 1989, when 18-time major title winner Martina Navratilova did it to Manuela Maleeva.
Williams won 53 of 71 points and dominated pretty much every statistical category. The first set took all of 19 minutes. The second was slower, lasting 33 minutes, but no less lopsided.
‘‘When you play against Serena,’’ Suarez Navarro said, ‘‘you know these things can happen.’’
In Friday’s semifinals, Williams will play 2011 French Open champion Li Na of China.
Asked in an on-court interview if her game is peaking, Williams replied: ‘‘No. Not yet. I hope not. I'm just trying to do the best that I can.’’
Well, that just happens to be rather good. Through five matches, Williams has dropped a total of 13 games. For comparison’s sake, know this: 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 Tuesday, which happened to be her 25th birthday.
Tough conditions, huh? That swirling wind in Arthur Ashe Stadium sure did not appear to bother Williams one bit. She wound up with 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.’’
When Williams did face a break point for the first time, 42 minutes and 11 games into the match, she came up with a big serve and raced forward for a simple putaway that she punctuated with a yell. Moments later came a second break chance, but even with Williams stumbling to the court, Suarez Navarro dumped the ball into the net.
It was that kind of night for her.
Earlier Tuesday, the fifth-seeded Li needed nearly 2½ hours to get past 24th-seeded Ekaterina Makarova of Russia, 6-4, 6-7 (5-7), 6-2.
On three occasions, Li went up a break in the second set, nearing eventual victory each time, but could not finish things. She then was up, 3-0, in the tiebreaker before faltering. Still, she recovered well and closed the match by taking the last four games, then joked that she would grab a bag of chips and enjoy watching Williams against Suarez Navarro.
Regardless of who she'd face next, Li made the point that what would be important is to focus on herself.
‘‘I mean, if you only think about what [your] opponent [is] doing, of course you already lose the match before you come to the court,’’ Li said. ‘‘For tennis you have to figure out what you have to do on the court, what you should do.’’
Li has only won one of nine career matches against Williams heading into Friday.
‘‘Tough, tough opponent,’’ Li said. ‘‘But is [a] good challenge to play against her.’’
The quarterfinals on the other half of the draw are Wednesday: second-seeded Victoria Azarenka of Belarus against 48th-ranked Daniela Hantuchova of Slovakia, and 10th-seeded Roberta Vinci against 83d-ranked Flavia Pennetta in a matchup between two Italians in their 30s.
While the other women in that section all advanced Monday, Azarenka’s fourth-round match against 2008 French Open champion Ana Ivanovic was postponed until Tuesday at 11 a.m. because of rain.
Azarenka refused to complain about playing her match a day later than the rest of her half of the draw.
She won’t wallow in misfortune, and that’s why Azarenka is still alive in the quarterfinals after dropping the first set in two straight matches. The second-seeded Belarusian rallied to beat Ivanovic, 4-6, 6-3, 6-4.
Ivanovic, the 2008 French Open champion, was whipping forehand winners in the first set. But then her serve deserted her, as it has before, and the 13th-seeded Serb was broken in nine of her last 11 service games.
‘‘This was the big difference because I felt like I could break her, but it was very frustrating that I was losing my serve constantly,’’ said Ivanovic, who had eight double-faults.
Indeed, Azarenka wasn’t much better, with nine double-faults of her own.Unable to serve out the match at 5-3 in the third set, Azarenka finally clinched the victory on her fourth match point.