Caeleb Dressel sets 100 butterfly world record, leaving one Michael Phelps mark left

American Caeleb Dressel set his first career world record and continued his run as one of the best 100m butterfly swimmers in history.

Dressel came in at 49.50 during the World Championships 100m fly semifinal in Gwangju, South Korea, on Friday. It best the mark set by Michael Phelps, who swam at 49.82 in August 2009.

Dressel holds six of the top 10 all-time men’s 100 butterfly performances, according to Swim Swam. His previous best was a time of 49.86, set in 2017, four-hundredths of a second behind the 23-time Olympic gold medalist.

Dressel, 22, made the mark with a strong first 50 that clocked in a half-second quicker than Phelps’ world record time. His back 50 pace was slightly slower than Phelps’. He’ll have a chance in the finals Saturday night to push the mark higher.

Phelps, 34, congratulated the new record-holder with an Instagram post.

Dressel replied, “I appreciate you and what you’ve done for us.” The two-time Olympic gold medalist (4x100m free, 4x100m medley in Rio) repeated as 100m freestyle world champion on Thursday and set an American record.

Phelps has one record left standing

It’s the second time this week Phelps has watched one of this world records fall at the world championships. They were all set during the “The Swimsuit War of 2009,” as reminded by NBC Sports Olympics writer Nick Zaccardi, when companies were racing to design the best performance-enhancing high-tech swimsuits.

Hungarian Kristof Milak, 19, broke Phelps’ decade-old 200m butterfly record by .78 seconds earlier this week.

Phelps told the New York Times:

“As frustrated as I am to see that record go down, I couldn’t be happier to see how he did it. That kid’s last 100 was incredible. He put together a great 200 fly from start to finish.”

Phelps’ last individual world record to stand is the 400m individual medley, which he had reset multiple times. It currently stands at 4:03.84 from the 2008 Beijing Games.

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