Marcel Latak, a 17-year-old who trains in Rancho Santa Fe, won the US Open boys' singles title Saturday, Sept. 12. He saved three championship points to defeat top seed Guto Miguel 3-6, 7-5, 7-6(13).

Latak is the first American to claim the trophy since Taylor Fritz won it in 2015. Fritz also trained in the San Diego area under the same coach, Christian Groh.

Ranked No. 41 in the world junior rankings entering the tournament, Latak eliminated five of the top 10 seeds at the USTA Billie Jean King National Tennis Center in Flushing, N.Y., according to the ATP Tour. He never lost a set before the final.

His path included wins over sixth seed Ziga Sesko, 10th seed Dimitar Kisimov, fourth seed Keaton Hance and second seed Jamie Mackenzie. Miguel, the world's No. 1-ranked junior, won the 2026 Roland Garros boys' title.

In the final-set tiebreaker, Latak led 7-2 and later 9-6 but watched both advantages slip away. He saved three championship points before hitting a backhand winner and falling to the court in celebration, the ATP Tour reported.

"I mean, I can't even believe this," Latak told Times of San Diego reporter Michael Lewis after his semifinal win Friday, Sept. 11. "If someone said to me a few weeks ago, 'Hey man, you're going to be in a Grand Slam final soon,' I'd be like, 'You're not right in the head.'"

Originally from Darien, Ill., Latak has trained in San Diego for the past 18 months under Groh, working mostly at a private court in Rancho Santa Fe and occasionally at San Dieguito Tennis Club in Encinitas. Groh previously coached Fritz from age 14 to 18 and also developed Brandon Nakashima, according to the San Dieguito Tennis Club website.

Groh told Times of San Diego on Sept. 11 that Latak's grit sets him apart. He called Latak a strong ball-striker with a beautiful backhand but said "it's his heart and his grit that really makes him stand out."

Latak's mother, Klaudia Latak, said the family often stays in Airbnbs or hotels during their San Diego trips. She called the week "a dream" after his semifinal victory.

Before arriving at Flushing Meadows, Latak had built momentum with a J300 tournament win in San Diego in March and another J300 title in Repentigny, Canada, giving him 11 consecutive match wins entering the US Open final, ZooTennis reported.

Latak is the 2025 USTA National Championship Boys' 16s winner and is committed to Stanford University's tennis program next August.

He also reached the boys' doubles final Saturday, partnering with 17-year-old Tanishk Konduri of Northern California. They were scheduled to face Aaron Gabet of France and Valentin Gonzalez-Galino of Spain on Court 12 after the singles final, according to USOpen.org.