Inarguably, Michael Phelps is the greatest Olympian of all time. After all, the 36-year-old has twenty-eight Olympic medals to show for it. Moreover, Phelps also holds the record for the most number of Olympic medals ever.

Phelps had set the world record for the fastest 100m butterfly in August 2009. With a time of 49:82, he set a phenomenal record that seemed unbreakable. In fact, it remained an unbreakable record until 12 years later when compatriot Caeleb Dressel finally demolished the butterfly record a decade later.

When Caeleb Dressel broke a ten-year record by Michael Phelps

It was in July 2009 when Michael Phelps broke compatriot Ian Crocker’s 100m butterfly record of 50.40. Crocker’s record had held up for almost four solid years. However, Phelps’ celebrations were cut short, when just a few weeks later, Serbian swimmer Milorad Cavic shaved off twenty-one milliseconds off of his new time.

Thus, at the same event, the World Aquatics Championships, Phelps took back his record time the very next day. Now, with a time of 49.82, Michael Phelps had set a new world record for the 100m butterfly sprint.

The record seemed unbeatable, and it surely proved to be, over the coming years. In fact, for an entire decade, nobody could beat Phelps’ time, until it came time for the 2019 World Aquatics Championships.

Rising American swimming star Caeleb Dressel, who was 22-years-old at the time, took to the water. All eyes were on Dressel as he took a phenomenal jump and lead the pack in South Korea. In fact, everyone watching roared in applause as he reached the halfway mark a full half-second ahead of Phelps’ world-record-setting time.

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On the way back, even the commentators were on the edge of their seats as Caeleb headed to the finish line. As Dressel’s hand touched the tiles, his time was 49.50, thirty-two milliseconds faster than Phelps’ 49.82 from ten years ago.

Caeleb’s reaction after breaking the record

After he broke the record, the entire world felt shocked, as nobody had thought that Michael Phelps’ record could ever be broken.

Dressel had broken the longest-standing world record in 100m butterfly history. Talking about “the standard that Michael set,” Caeleb had shared that he “wanted to go after it”.

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Moreover, he also wished that it made Phelps, the greatest swimmer in history, proud. “I hope he was happy watching me do that,” Caeleb had shared.