Rowan Cox Lowers 17-18 National Age Group Record in 100 Butterfly, Finishes Third at Nationals
In the center lanes of the men’s 100 butterfly at U.S. Nationals, Ilya Kharun overtook Caeleb Dressel in the final 25 meters on the way to posting the fastest time in the world this year. Dressel, the Tokyo Olympic champion and world-record holder, finished second in his quickest time in more than two years. Just off the pace was Rowan Cox, an 18-year-old set to begin his college career at the University of Texas this fall.
Cox touched the wall in 50.64, concluding a day when he vaulted himself into the national conversation in the event. He arrived at Nationals with a best time of 52.59 before dropping all the way to 51.42 in prelims. He had another leap waiting at night, making himself the seventh-fastest swimmer in the world this year.
Cox also became the fastest 18-and-under swimmer in U.S. history, clipping the previous 17-18 National Age Group record of 50.70 set by Thomas Heilman in June 2025. Before Heilman’s emergence, the record had belonged to Michael Phelps at 51.10, a time he achieved in a silver-medal-winning effort at the 2003 World Championships.
Moreover, that time makes Cox the sixth-quickest American swimmer of any age, behind only Dressel (49.45), Phelps (49.82), Shaine Casas (50.24), Ian Crocker (50.40) and Dare Rose (50.46). A time of 50.64 would have finished first or second at every previous U.S. selection meet, and it’s unclear if any swimmer representing the U.S. next month at the Pan Pacific Championships, a group including Casas, Rose and Heilman, will be able to match or surpass that mark.
Even with Kharun and Dressel set up as the heavy-hitters in the 100 fly moving forward, Cox has put himself in position to contend with the big names if he can continue his quick improvement.
