It's a world record that might only last a day. Still, the U.S. mixed 4x400 meter relay team owns it.
The team of Vernon Norwood, Shamier Little, Bryce Deadmon and Kaylyn Brown finished the four laps Friday in 3 minutes, 7.41 seconds to break the mark of 3:08.80 set at world championships last year.
All the record did was place the Americans in Saturday's final, where the record — in an event that is only 5 years old — will be in jeopardy once again.