Another day, another record smashed. Sydney McLaughlin lowered her own world mark after chasing down her great rival, Dalilah Muhammad, for an American one-two in the final of the 400m hurdles on Wednesday. One day after Norway’s Karsten Warholm did the same in the men’s race, the 21-year-old showed just how much the super-fast Tokyo track, with its extra bounce, is helping the hurdlers.

Muhammad, the defending Olympic champion, set off at a furious pace and looked to have victory in her sights coming out of the bend. But McLaughlin, sitting easily on the shoulder of a Dutch racer, surged through on the inside to overtake her rival at the final hurdle before kicking away to the line. She finished in 51.46, easily beating the world record 51.90 she set at the U.S. Olympic trials. Muhammad came home in 51.58, the second-fastest time ever, while Femke Bol took bronze in 52.03.