FOURTH seed Naomi Osaka is through to the Round of 16 at the US Open after knocking off teenage Ukrainian, Marta Kosyuk in three sets. The match lasted two hours and 33 minutes before Osaka could safely advance through to the fourth round. The 18-year-old Ukrainian won a second set tiebreaker and forced Osaka onto the back foot at times, drawing praise from the Japanese star post-match.

“I’m kind of scared of (how) good she’s going to be in the future,” Osaka said. “My biggest takeaway from her game is that she didn’t back down from me or from the speed of my ball, which for someone that young is kind of amazing… The first set went [my] way, and then she could have faded in the second set. Of course in the third set towards the end I feel like physically I was better, and I was, of course, more experienced. “But, yeah, I feel like she’s definitely going to be dangerous.”

Kostyuk actually outhit Osaka in a surprising result, slamming home 36 winners to Osaka’s 30, but also had 13 more unforced errors (51-38). Osaka’s ability to dominate off her first serve, with a 82 per cent record, as well as a 51 per cent efficient off her second serve was quite impressive. Additionally, Osaka broke five times from 21 chances, while Kostyuk only had the one from eight chances.

“I was very displeased with how I was performing towards the end of the second set,” Osaka said. “The thing that made me most displeased was probably the decisions that I was making and the fact that I started becoming way too passive and hoping that she would make an unforced error. “For me, I felt everything was going really well for her during the tiebreak. And I remember she came to the net, and I hit it as hard as I could towards her, and she made it, and for me I was just, like, whoa, this is unbelievable.”

Osaka now takes on 14th seed Anett Kontaveit in the Round of 16. The Estonian defeated Poland’s Magda Linette in straight sets 6-3 6-2 in a convincing victory. Also through to the Round of 16 was eighth seed Petra Martic who defeated Varvara Gracheva 6-3 6-3. Gracheva showed her damaging ability with a come-from-behind Round 2 win over Kristina Mladenovic from 6-1 5-1 down, only to come back and win, 1-6 7-6 6-0. But it was Martic who got on top and made sure she kept on top of the counterpuncher.

“I played her a couple of weeks ago and I knew it was going to be a tough match,” Martic said post-match. “She likes to grind, she’s really quick and she’s a great counterpuncher. “I definitely had to work today and I’m pleased I got the win in straight sets. “I managed to change up the rhythm well. “When she plays at the same rhythm she doesn’t make many mistakes and I was getting pulled into that game. “My serve always helps, this court is a bit slower so my kick works well and I think that was key.”

The Croatian will take on Kazkahstan young gun, Yulia Putintseva who won through in a tight three sets over Belarusian Aliaksandra Sasnovich, 3-6 6-2 6-1. In that top quarter of the draw, unseeded American Jennifer Brady continued her dream month win a win over Caroline Garcia, 6-3 6-3 to now face Grand Slam winner Angelique Kerber 6-3 6-4 in the quarter finals. Kerber was able to defeat talented American Ann Li 6-3 6-4 to move through to yet another major quarter final.

In the final two matches of the day, Shelby Rogers won the battle of the Americans, defeating compatriot Madison Brengle 6-2 6-4 to advance to the Round of 16 where she will play Petra Kvitova following the sixth’s seed’s win over another United States representative in Jessica Pegula.

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