Mighty Phelps stunned on record-breaking day

Rio de Janeiro : Singaporean outsider Joseph Schooling stunned the great Michael Phelps and Almaz Ayana obliterated the long-standing women's 10,000m record on a day of surprises at the Rio Olympicson Friday.

Phelps was seeking his 23rd Olympic gold in the 100m butterfly but Schooling, 21, relegated the legendary American to silver -- which he shared with both Chad le Clos and Laszlo Cseh.

"I'm just ecstatic. I don't think it has set in yet, it's just crazy," said Schooling, who set a new Games record of 50.38sec.

"You know, breaking the Olympic record, and it was a thrill to swim against Michael Phelps and all all those guys."

It was among a number of shocks as 1,500m ace Sun Yang flopped out of his pet event and defending champions USA crashed out of the women's football.

Ethiopia's Ayana smashed the 23-year-old 10,000m record by nearly 14 seconds as the athletics competition got underway without Russia, whose track and field team are suspended over a doping scandal.

US swimmer Katie Ledecky also made history as she completed the first 200m, 400m and 800m treble since 1968 -- and again in world-record time.

America's latest swimming star won the 800m by a distance in a time of 8min 04.79sec, beating her own world record of 8:06.68 set in January.

Elsewhere cyclist Bradley Wiggins became Britain's most decorated Olympian of all time and Rafael Nadal, returning from a wrist injury, won men's doubles gold.

The Rio Games also reeled from three doping cases as a Chinese swimmer was suspended and a Bulgarian weightlifter and Polish runner were kicked out.