Adam Peaty was absent as Team GB surrendered their Olympic crown and world record in the mixed 4×100 metres medley relay final to the United States.

Peaty helped Team GB win the inaugural event at Tokyo 2020 but he missed Friday’s heats after a positive Covid test on Monday morning, having bagged silver in the men’s 100m breaststroke the night before.

While Peaty featured in the men’s 4x100m medley relay preliminaries on Saturday morning and described how he has had the “worst week” physically, he was conspicuously absent from the evening’s mixed final.

Kathleen Dawson, James Wilby, Duncan Scott and Anna Hopkin finished a disappointing seventh as the USA claimed gold in three minutes and 37.43 seconds – 0.15 secs quicker than Team GB were three years ago.

Peaty’s focus is instead on the men’s final on Sunday although he admitted he will not be firing on all cylinders, having also been battling other ailments including an ear infection in recent days.

“It’s been a rough, rough week but hopefully we’ll find our way through the next 36 hours,” said Peaty.

“(It’s) probably (been) the worst week of my life in terms of how my body is – and that is no exaggeration.

“Everything’s come at once and since Covid, I’ve been waking up every day with a different thing.

“The medical team has been brilliant and it’s just a victory getting on that starting block. Now hopefully, that will give my body a nice, little push for tomorrow.”

Peaty, alongside Oliver Morgan, Joe Litchfield and Matt Richards, finished second in their heat and qualified fifth fastest overall, with France – led by Leon Marchand – topping the time sheet.

Marchand, who collected his fourth individual gold medal on Friday night, swam the breaststroke leg in a separate heat and is now set for an eye-catching showdown against Peaty on Sunday.

But Peaty, whose leg of 59.16 seconds was just 0.11 secs slower than his time in last week’s men’s 100m breaststroke final, attempted to temper expectations.

“I’m glad I’ve got a heat swim,” added Peaty. “It’s my first hard stuff since the final on Sunday last week.

“If I’m not well, I’m not well. I’ve been brought up in the system by (coach) Mel (Marshall) that if you’re not well, you still go.

“I’ve only got two days left. I’m not going to be 100 per cent, I know that, but I’ll give my best effort and that will hopefully give me a nice time.”

Katie Ledecky made more history as she won the women’s 800m final, joining Michael Phelps as the only swimmers to claim gold in the same event at four successive Olympics.

This was the American’s ninth gold, equalling the record for a female Olympian with former Soviet Union gymnast Larisa Latynina, and her 14th medal overall in a breathtaking career.

Summer McIntosh looks to be swimming’s next superstar and the 17-year-old Canadian won her third gold at Paris 2024 with victory in the women’s 200m individual medley final. Team GB’s Abbie Wood was fifth.