Michael Phelps of North Baltimore Aquatic Club rose to the challenge put forth by Chad Le Clos, after his gold-medal performance of 50.56 in the 100m butterfly at the 2015 World Championships in Kazan, and posted yet another World-leading time, winning the U.S. National title in 50.45. That beat Le Clos’ winning time by .11.

Phelps was relatively slow off the blocks, but he made up for it with an incredible wall at the 50 and perhaps the best second-half of his career.

r 0.81 │ 24.10 / 26.35 = 50.45

Le Clos’ splits in Kazan, by comparison, were:

r 0.64 │ 23.72 / 26.84 = 50.56

After his win, Le Clos threw down the gauntlet, saying amongst other things, “Michael Phelps has been talking about how slow the butterfly events have been recently. I just did a time he hasn’t done in four years. So he can keep quiet now.”

In the post-race interview, Phelps responded with: