RIO DE JANEIRO - Michael Phelps, the most decorated athlete in the history of the Games, raced in the first final of his last Olympic stand on Sunday.
He helped the USA seal 4x100m freestyle victory in 3mins 9.92sec, extending his record medal haul to 23 Olympic medals - 19 gold.
Phelps now has a joint-record fourth medal in this event after also winning gold in 2008, silver in 2012 and bronze in 2004. Former teammate Jason Lezak has a gold, two silver and a bronze from 4x100m free races from 2000-2012.
Defending champions France took silver in 3:10.53. Australia claimed bronze (3:11.37).
Phelps swam the second leg and recorded the best reaction time (0.08sec) of the night. He clocked a personal-best 47.12sec and was the second-fastest American swimmer behind anchor Nathan Adrian (46.97sec).
Caeleb Dressel and Ryan Held completed the team, who were desperate to regain the title for the USA after finishing second at the 2012 London Games.
"We wanted that race back so badly. I played (the London 2012) race for the guys in the room the other day," Phelps said.
"In 2008 we had a great one, in 2012 we fell off a little bit. My last 4x100 relay, it feels damn good to get a win. It was the fastest 100m free of my career."
The 31-year-old is competing in his fifth Olympics. But he admitted that the atmosphere at the Olympic Aquatics Stadium was like no other.
"On the block (while Caeleb was coming in) I thought my heart was going to explode," he said. "I was so hyped, so excited.
"Having the amount of excitement, cheering in the stands during that race, I don't know if I have heard anything like it."
Phelps still has three individual events to go - the 100m and 200m butterfly and 200m individual medley.
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