Michael Phelps is done.

He probably has to tell everyone that a few more times before we actually believe him. After all, he said he was retiring after the 2012 Olympic games in London.

But Sunday, Phelps told NBC Nightly News host Lester Holt that he really is done. He has hung up his suit after winning 28 Olympic medals, 23 of them gold, in five Olympics.

Phelps told Holt that he woke up "happy" Sunday after swimming in his final Olympic race the previous night. Phelps swam the third leg of the men's 4x100 medley relay, winning his final Olympic gold medal.

Even after the race, he had to keep telling his teammates that he was, in fact, done. But they were not the only ones bugging him about it.

He also had to convince his mom.

When Phelps saw his mother, Deborah Phelps, after the race, she was still persisting about his future.

"I said, 'Mom, I'm done,' " Phelps told Holt.

"What about the 100 fly? Relay?" Phelps said his mother asked.

But Phelps stuck to his answer: There will be no trek to Tokyo.

To watch the full interview: Click Here.

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