Botswana edged out the USA in a thrilling men's final as Sydney McLaughlin-Levrone anchored the American women to a championship record.

On the final day of the World Athletics Championships in Tokyo, the men's and women's 4x400m relays unfolded in wet and difficult conditions.

After a chaotic qualification round the day before where the United States – Olympic champions in the event – found themselves out of the final after a disrupted heat but a solo re-run on Sunday morning gave them a second chance. Taking that opportunity, they combined to run 2:58.48 to earn lane one in the final.

During the final, Rai Benjamin, handed the baton in first position, carried their hopes into the final leg. But Botswana’s Busang Collen Kebinatshipi, the newly crowned 400m world champion, had other plans. In a thrilling finish, Kebinatshipi chased down Benjamin in the closing metres, guiding his team to gold in 2:57.76 - just ahead of the Americans, who were caught at the line and had to settle for silver in 2:57.83.

South Africa, anchored by Zakithi Nene, were closing fast and crossed the line in the exact same time as the USA, but were awarded the bronze on thousandths of a second.

Great Britain, meanwhile, were never in medal contention. Their team of Lee Thompson, Toby Harries, Lewis Davey (who replaced Seamus Derbyshire), and Charlie Dobson, had qualified automatically for the final after a disqualification from Australia in the heats. Matthew Hudson-Smith's absence was noticeable and the British quartet ultimately finished sixth in 3:03.05.

In contrast to their Olympic bronze medal in Paris, Great Britain were absent from the women's 4x400m final after finishing last in their heat and failing to advance.

The spotlight in the final was on Sydney McLaughlin-Levrone, the 400m flat world champion and world record-holder in the 400m hurdles, who anchored a completely fresh USA team.

None of the four athletes - Isabella Whittaker, Lynna Irby-Jackson, Aaliyah Butler, and McLaughlin-Levrone - had featured in the heats, with the squad opting for a full change in personnel for the final.

By the time the baton was handed to McLaughlin-Levrone on the final leg, the USA already held a commanding lead. She maintained the margin with ease, bringing the team home in a championship record time of 3:16.61.

Behind them, the race for silver was between Jamaica and the Netherlands. Jamaica held second place as Nickisha Pryce took over on the anchor leg, while the Netherlands relied on 400m hurdles world champion Femke Bol to chase them down.

Despite Bol's effort, the gap was too large to close, and Jamaica secured silver in a season's best of 3:19.25. The Netherlands completed the podium in third, also with a season's best of 3:20.18.