The United States team broke their own world record in the 4x400 mixed relay in the opening heats at the Paris Olympics on Friday, crossing the line in three minutes 7.41 seconds.
They set the previous mark of 3:08.80 at the 2023 World Championships in Budapest.
The U.S. led midway through the second lap in a text book performance, overcoming a fast field in the opening heat in which four national records were broken on top of the world mark.
"I've gotten quite a few practices in over the last few days and we've just gotten better," said Shamier Little, who ran the second leg for the Americans. "We've got great chemistry."
The French team were willed across the finish by a partisan home crowd at the Stade de France, as they held off Belgium and Jamaica to finish second in 3:10.60 in the rarely contested event.
The 4x400 mixed relay final is set for Saturday.
