A day after a near-disaster with a dropped baton, defending champions the United States made no mistake on Friday when they won the women's Olympic 4x100 metres relay and Allyson Felix became the first woman to collect five athletics gold medals.

The U.S. team of Tianna Bartoletta, Felix, English Gardner and Tori Bowie clocked 41.01 seconds, the second-fastest time ever after the U.S. world record set in London four years ago, to beat Jamaica on 41.36 and Britain on 41.77.

"It's very special. It was great to join these women tonight. It's just a very unique experience," Felix said of her milestone.

"The adversity yesterday made us even more determined. We just kept fighting the whole way through," she said, referring to the 'crazy freak accident' in the Thursday morning heats when the baton dropped to the ground as she handed over to Gardner.

The Americans appealed successfully, arguing that Felix had been impeded by a Brazilian runner, and went through at China's expense after being allowed to race by themselves in a solo heat in the evening.

They sailed through in the final despite the disadvantage of racing in the tightest lane, number one, fuelled by determination not to repeat Thursday's mishap.

"It really made us focus and buckle down on executing the race," Bartoletta said.