NEW YORK, NY, USA - No.2 seed Ashleigh Barty has returned to the second week of the US Open, coming through a competitive match 7-5, 6-3 over No.30 seed Maria Sakkari in one hour and 26 minutes.

"I think overall today there were parts of the match I was really happy with," Barty said during her post-match press conference. "I feel like a few of the things that I've been lacking over the last month kind of came together a little bit today. I felt like I served a lot better, controlled the ball off the first strike more often than not. In the bigger moments, I felt like there was some better stuff there."

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The Australian made her debut in the fourth round of a Grand Slam here last year, losing to Karolina Pliskova, but arrives this year as the front runner to return to the World No.1 spot after the tournament - with Naomi Osaka needing to defend her title and Pliskova requiring at least a semifinal to overtake Barty. Today's win - Barty's fourth in five meetings, and third this year, over Sakkari - will boost her hopes further. It also means that the 23-year-old is the only player to have reached the second week of every major in 2019.

"That's what we aim for, it's what we strive to do, is to try and do the best we can every tournament," said Barty. "Particularly at Slams, to make that a bit of a focus point, to try to be ready, to try and make sure that I'm giving myself the best chance to go deep in the Slams. Really happy to be into another second week."

"I feel like every day I've been getting better and better," Barty added. "I still feel great. There's a few big months left in the season. We're looking forward to it."

Despite her head-to-head lead, the Roland Garros champion's most recent encounter with Sakkari just two weeks ago in the Cincinnati quarterfinals had gone to three sets, so a narrowly contested opener today was not entirely unexpected. Both players relentlessly probed each other's games, attempting to manoeuvre the ball into awkward positions, and ultimately in a battle between Barty's biting slice and Sakkari's heavy topspin, it was the former that won out.

Indeed, Barty would find that slicing to the Greek player's forehand in particular would frequently draw a mistake, as Sakkari racked up 25 unforced errors to only seven winners in the first set. The Miami and Birmingham champion also evinced a touch more imagination in her point construction, coming up with a wrongfooting backhand slice winner at one stage, and a more effective serve with which she tallied five aces to Sakkari's none.

Consequently, Barty would capture the first break in the third game - and though a rare volley error, her only one of the set, handed the Rabat champion the break back for 4-4, more errant forehands from Sakkari enabled Barty to take the final two games of the opening act from 5-5.

Both players would continue to carve out opportunities on each other's serves as the second set progressed, but it was once again Barty who was more efficient at taking them: over the course of the match, she would convert three of her six break points, while Sakkari would take only one of four.

Having saved a break point in the fourth game with her seventh out of 11 aces today, Barty struck in the next game, an excellent angled pass bringing up a chance - promptly taken as Sakkari's forehand went awry once more.

The Australian Open quarterfinalist had increased her first serve percentage from 41% to 54% in the second set, and this greater comfort behind her delivery saw her consolidate her lead comfortably. Serving to stay in the match, Sakkari would fall away rather limply, committing four straight unforced errors to take her total to 38 - and sealing her seventh loss in seven Grand Slam third round appearances, a record among active players.

Barty, though, will have the opportunity to make her third major quarterfinal of the season against No.18 seed Wang Qiang of China, who defeated Frenchwoman Fiona Ferro in straight sets on Friday.

"Obviously [Wang is a] very tough competitor, moves extremely well," Barty stated. "When the ball is in her strike zone, she can go both ways, cross and line off both wings. I think it's going to be an incredibly physical match, a match where I need to make sure that I serve well and bring variety in as much as I can."