His mobile phone didn’t stop buzzing. Each time Zangar Nurlanuly started a sentence, or actually even before he sat down for an interview Tuesday, his iPhone would ring or buzz.

He grabbed it once, saying something very excitedly and laughing, then put it down and tried to play it cool. He then gave the phone to his sister to watch while he answered questions.

But he couldn’t play it cool for long. The 17-year-old was smiling and giddy after what he describes as “the biggest win of his career.”

Calm on big points and finishing the match with a service winner, Nurlanuly knocked No. 12 seed Alan Wazny of Poland out of the US Open Junior Championships following a 6-4, 6-4 triumph to reach the third round at a Grand Slam for the first time. 

Ranked No. 54 in the ITF World Tennis Tour boys' rankings, Nurlanuly, from Kazakhstan, has gone further than he ever has before and will now face No. 6 seed Oskari Paldanius of Finland.

“It just feels great to have this kind of result at such a great tournament,” Nurlanuly said, as his phone buzzed again.

“I just wanted to play my game and be aggressive. I was just enjoying myself so much out there, and I don’t even know how that happened. It’s very exciting.”

Nurlanuly is the latest player from his country to be having a terrific tournament here in Flushing Meadows. Alexander Bublik, the No. 23 men’s seed, advanced all the way to the fourth round before losing to Jannik Sinner on Monday night, while Elena Rybakina, the women’s No. 9 seed, also reached the fourth round before losing to Marketa Vondrousova.

“We are really coming on, and there are lots of good players from Kazakhstan in juniors right now,” Nurlanuly said, alluding to No. 24 Amir Omarkhanov.

Nurlanuly’s tennis journey started in a funny way; born and raised in Almaty (population 2.2 million), he said his father, Nurlan, was an avid recreational player, and one day Zangar, at age 4 or 5, went to a match with his Dad.

When they came home, Zangar grabbed a racked and smashed a ball so hard it broke a glass of water in their home.

“So the next day his dad said, ‘we’re going to get you some tennis lessons, so you don’t break anything else in the house,’” Zangar recalled with a chuckle.

For the past five years he’s trained in Slovakia, and now is coached by Alexander Somogyi.

“We worked a lot on the mental part with him: That was his biggest issue because the talent is there,” Somogyi said after the match.  “He showed his courage today, I’m very happy for him because this was an important win.”

Nurlanuly fell in the first round of both Wimbledon and Roland Garros this year, while reaching the second round of the Australian Open.

He said he’d give himself “about 30 minutes” to celebrate the win, and then it was time to prepare for his doubles later (he and partner Damir Zhalgasbay won their first round match).

“It’s so amazing to be here and get to keep playing here,” Nurlanuly said. “Every kid has a dream of winning a Grand Slam, right? So it’s exciting to still have a chance.”

A full list of results from the 2025 US Open Junior Championships is available here.