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  • Mu outkicked prerace favorite Raevyn Rogers for the win.

Athing Mu collapsed in disbelief next to the electronic scoreboard at the Ocean Breeze Athletic Facility in Staten Island. The 16-year-old had just outkicked prerace favorite Raevyn Rogers to win the 600 meters at the 2019 USATF Indoor Championships.

Next to her time of 1:23.57 was two letters: AR. She earned an American record.

“I’m super shocked. At first when I was taking a picture next to the timing, I thought it was just another high school record,” Mu told Runner’s World. “I looked back and it said ‘AR’ and I also didn’t see the time, 1:23, so I was just like oh my gosh, it’s crazy. It literally brought me to tears.”

The pug-loving, braces-wearing New Jersey girl says she is “childish” and feels closer to 14 than 16. Only one of her brothers—Mu is one of seven siblings—was able to see her set the national junior record in the 600 meters in the preliminary heats on Saturday, since her parents and six other siblings had other work and school commitments. Just her coaches were there when she won a title previously held by Olympians Ajee’ Wilson and Alysia Montaño.

“The time surprised me,” said King Jennings, head coach of the Trenton Track Club. “I thought it would take about 2:25, maybe 24.9, somewhere around there it would take to win it. But the 23 just blew my mind.”

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“She has a bright future,” Rogers said after the race. “Ajee’ already knew about her, so just my impression of her is she’s a great person. It makes a difference when someone is a great person away from the track, and she’s just a sweet girl, she really is.”

Mu will compete at the New Balance Nationals next weekend. She hopes to compete in this summer’s USATF outdoor national championships, though she first has to check her family’s schedule to see if she can go.

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Derek Call
Video Producer

Since becoming a video producer for Runner’s World in 2014, Derek A Part of Hearst Digital Media Meb Keflezighi and Desiree Linden’s Boston victories and Amy Cragg’s win at the 2016 U.S. Olympic Marathon Trials, and Galen Rupp and Shalane Flanagan breaking the tape in Chicago and New York, respectively.