Rio Olympics 2016: Michael Phelps says 'there wasn't a shot in hell' of losing out on 21st medal

Michael Phelps won two more finals to take his historic all-time record load to 21 golds and cement his legendary status.

Phelps beat Japan's Masato Sakai by just four hundredths of a second to take the 200m butterfly and later anchored the US 4x200m freestyle relay team to victory.

At 31 — the oldest individual Olympic swimming gold medalist ever — Phelps is still the master of the pool.

Michael Phelps poses on the podium during the medal ceremony. Getty Images

After claiming his 20th title in five Olympics — beating old rival Chad le Clos in the process — Phelps stood in the water striking a pose like a Roman emperor, soaking up the acclaim.

“I honestly I don't know at this very moment where that stands,” Phelps said when asked how it compared to some of his other great nights in the pool.

“It's kind of been a crazy last couple days. I know that was probably one of my most challenging doubles.

"That being my very first Olympic event, to be able to win it at my fifth Olympics is pretty special."

During the customary stroll around the pool to pose for photographers after 200m butterfly, Phelps broke ranks and bounded into the stands to plant a kiss on Boomer, the son who symbolizes just how much Phelps' life has changed since a second drunken-driving arrest two years ago.

"I wanted to hold him longer," Phelps said. "It's good to see he's awake. He usually sleeps all the time."

Phelps retired after the London Games, so it looked like he wouldn't get a chance to make up for his defeat. But when he decided about a year later to start competing again, the 200 fly was clearly the title he sought more than any other.

"This is the race I really wanted back," he said.

The 200m butterfly was his first world record in 2001 and he was determined to win back the Olympic title he lost to South Africa's Chad Le Clos in 2012. But Phelps said that was also the last time he would race it.

“That event is kind of like my bread and butter and that was the last time I’ll ever swim it. Having that come to an end, it's weird, it's crazy to think about,” Phelps said.

"There wasn't a shot in hell I was losing that race and if I did I was leaving everything in the pool.

"Just being able to see the one by my name again, one more time in the 200 fly. Couldn't have scripted it any better."

No other Olympian has more than nine golds.

"That's a lot of medals," Phelps said, shaking his head. "It's just insane."

With inputs from agencies