Okolo improved her former personal best and NCAA record of 50.03 by more than three-tenths of a second to encroach on Felix's 49.26 PR, which is the third-fastest time ever run by an American. Out of the top seven times ever run by collegiate women, Okolo now owns three of them.
Only nine women in the world have ever broken the 49-second barrier, and two of those spots belong to US Olympians Sanya Richards-Ross and Valerie Brisco.
Okolo's record-breaking performance ranks No. 12 all-time in the US, and is just .07 away from landing her in the top 10.
Flashback to this time last year when Okolo took down Olympic 400m gold medalist Richards-Ross at the Michael Johnson Classic: