Garbiñe Muguruza is a firm favourite now for the title, having won Wimbledon and Paris and probably playing the most authoritative tennis of her life.
The third seed was riding a seven-match win streak through the first two rounds in New York after winning the US Open Series stop in Cincinnati.
Bizarrely, this third-round showing represented Muguruza’s best-ever US Open performance; in four prior tries, she had never been beyond Round 2.
I knew I had a tough match and was expecting someone who plays very good, I take every match [at a time] and I am concentrating on my next opponent, my next opponent, my next opponent Garbine Muguruza
In trying to better that, the Spaniard had to deal with Magdalena Rybarikova of Slovakia, the No 31 seed, who posted her own best Grand Slam showing in July, rolling across the lawns of London before getting mowed down by Muguruza in the semis.
Rybarikova, 28, had twice before reached the third round here but has lost in Flushing’s first round in each of her last three appearances.
Including this summer’s grapple on the grass, the two women had met four times, with Muguruza holding a 3-1 edge, and the contest promised to be tight at best.
It took place on the temporary Louis Armstrong Stadium, built to fill in while the new stadium is rebuilt alongside, and it has fast become a favourite among players and spectators alike with its overhanging trees and airy atmosphere.
In a rematch of the Wimbledon semi-final, the 23-year-old battered her opponent from the outset, first blood falling to Muguruza, who broke as soon as the match got under way, held and broke again to go 3-0 up, Rybarikova’s frustration clear.
Things did not improve as the Spaniard extended her lead to 4-0 before the Slovakian got herself on to the scoreboard.
It was short-lived and Muguruza closed out the set, 6-1, in just 27 minutes.
She met her first real resistance in the opener of the second in which she saved numerous break points but was unable to convert on her own game points until, eventually, she dropped her serve.
She broke back to restore the deficit, went ahead again by holding for 2-1, and then broke again to love to dominate 3-1.
Rybarikova had few answers for Muguruza’s onslaught as the World No 3 grew in confidence and used her superior fire power to greater effect, going up 15-40 on the Slovak’s next delivery.
She saved the first with fine serve-volley winner but drilled her forehand into the net to give up the game.
Muguruza served her second ace and nailed another to give her match point at 40-15, winning through with another winner, 6-1 6-1, in one minute over the hour.
“I knew I had a tough match and was expecting someone who plays very good,” she said.
“I take every match [at a time] and I am concentrating on my next opponent, my next opponent, my next opponent!”
She is looking like the potential champion here in New York with every appearance and has yet to lose a set at Flushing Meadows this year, and only nine games so far.
Next up for Muguruza is two-time Wimbledon champion Petra Kvitova, the 13th seed, who beat 18th-seeded Caroline Garcia 6-0 6-4.
Suárez Navarro survives against Makarova
Another Spaniard, Carla Suárez Navarro scored an impressive victory over Ekaterina Makarova to reach the fourth round after surviving a roller-coaster of a match on Court 5.
When Makarova saved break point with a backhand winner while down 6-1, 2-0 against the Spaniard, and then proceeded to claim six of the next seven games, it appeared that everything was going the Russian’s way.
Suarez Navarro, the second-ranked Spanish woman in the world, however, righted her ship, jumping to another lead in the third set and not relinquishing it again, advancing to the fourth round of the US Open for the second year in a row, 6-1 3-6, 6-3, in 101 minutes.
After a sloppy first set littered with mistakes, the Russian making 11 more unforced errors than she hit winners in the opener, the match became far more even.
The world No 40 made just 6 unforced errors in the second set after the second game.
When Suarez Navarro jumped to a 3-0 lead in the decider, she would not get reeled in again.
The 29-year old Makarova battled hard, forcing two deuces in an attempt to break back while down 2-0 and 3-1, but she could not get any closer.
Suarez Navarro, who is 28, won 48 percent of return points in the third set, breaking twice to clinch the victory.
It has not been an easy season for Suarez Navarro, who parted ways with longtime coach Xavier Budo, with whom she worked for 10 years, in July.
After a lacklustre summer hard-court season in which her best result was making the third round in Cincinnati, Suarez Navarro is finding the form that helped her to a career-best year-end finish of No 12 in 2016.
Stephens ousts Barty
Sloane Stephens eliminated the last Australian in the women’s singles draw on Friday, beating Ashleigh Barty, 6-2 6-4, in the third round.
It was the first meeting for Barty, the 2011 Wimbledon girls’ singles champion who took a hiatus to pursue cricket, and Stephens, who is on the comeback trail after right-foot surgery in January.
Stephens now has the opportunity to surpass her deepest run at the US Open, matching her 2013 appearance in the round of 16, where she lost to Serena Williams.
Friday’s match in the temporary Louis Armstrong Stadium, however, was not her best, with 42 percent of the points resulting in unforced errors; Stephens simply made fewer of them – 21 compared to Barty’s 31.
Stephens also had a hard time gaining momentum on her service game, digging herself a 0-30 hole on 5 of her 9 service games.
Barty was unable to capitalise on her break points, losing 7 of 8 in the first set and 1 of 3 in the second.
Stephens, ranked No 83 in the world, faces Julia Georges in the fourth round and while Barty exits the singles draw, she is the No 6 seed in doubles with countrywoman Casey Dellacqua.
Georges sees off Kunic
Elsewhere, on Court 5, another Russian, Aleksandra Kunic, the vanquisher of Johanna Konta in round one, took on the talented Italian Julia Georges, and lost, 6-3 6-3.
Georges is the No 30 seed and will play Sloane Stephens in the next round.