RIO DE JANEIRO -- Michael Phelps wasn't about to be stopped. Not even by his biggest rival.
Phelps blew away Ryan Lochte -- and everyone else, for that matter -- to win his fourth gold medal of the Rio Olympics and 22nd overall with a victory in the 200-meter individual medley Thursday night.
This was touted as the last showdown between two of America's greatest swimmers, though there's never been any question about which one had the upper hand.
Phelps became the first swimmer ever to win the same event at four straight Olympics, and he always left Lochte trailing in his wake. Phelps finished a full body-length ahead of the field with total dominance on the breaststroke and freestyle legs, finishing in 1 minute, 54.66 seconds.
Lochte didn't even make it to the podium this time, after taking two silvers and a bronze behind Phelps at the last three Olympics. He led at the midway point but faded to fifth.
Japan's Kosuke Hagino took the silver, while China's Wang Shun claimed the bronze.
The rivalry between Phelps and Lochte spans 12 years, but simply calling them rivals is only half the story, CBS News correspondent Ben Tracy reported.
The two have been competing together and against one another for four Olympics. For 13 years, the veteran swimmers have dominated the 200-meter individual medley, CBSSports.com reported.
"The competitive environment between those two guys has always been good," said Gregg Troy, who coached both swimmers at the 2012 Olympics. "Even at their own testament, they both say they bring out the best in each other. And I think there's a mutual respect, but also they're very competitive and neither one wants to give in or go home."
Phelps made his Olympic debut in Sydney in 2000 at just 15. Lochte showed up four years later in Athens, and ever since, has had to swim in the shadow of the most triumphant Olympian ever.
If it weren't for Phelps and his 25 medals, Lochte would be the most decorated male Olympic swimmer of all time. He's won 12 medals, one more than Mark Spitz, the star of the 1972 games.
"He's the hardest competitor I've ever had to go up against and he's not likely to back down. And I'm not either," Lochte said.
But at the U.S. Olympic swim trials this summer, Phelps said their relationship has evolved.
"Honestly, I think we've both just grown up. I do feel like I talk to him more and joke around with him more than I really did in the past," Phelps said.