A local swimming school is cheering on one of their own: Anthony Ervin, the first swimmer to win gold medals 16 years apart. NY1's Erin Clarke filed the following report.

35-year-old Anthony Ervin became the oldest individual swimmer in Olympic history to win a gold medal, when he finished first in the 50-meter freestyle in Rio on Friday.

He tied for gold in that event during the 2000 Sydney Games at age 19.

Both times he was being cheered on by friends from New York.

"It was a mix of disbelief, joy, excitement. Just unbelievable," said Lars Merseburg via Skype.

Merseburg is the co-founder of Imagine Swimming, a swimming school in the city. He was on the swim team with Ervin at the University of California, Berkeley.

But then Ervin was out of the sport for about a decade as he battled drug and alcohol addiction.

That's when his friend suggested he move to the city to teach kids how to swim.

Ervin came to work for Merseburg's "Imagine Swimming" school, which has locations in Brooklyn and Manhattan.

"He came to New York after kind of being lost," Merseburg said. "He quit swimming in 2002 after the World Championships and was kind of just floating around, doing odd jobs, working at tattoo parlors, riding his motorbike, dropped out of school."

But teaching kids may have helped Ervin find his way back to competitive swimming.

"They brought a spark to it that I think he had when he was a younger child and then lost," said Brendan O'Melveny, the director of pool management and staff training.

The children learning how to swim at Imagine's TriBeCa flagship on Saturday don't know Ervin personally, but he and the rest of Team USA are inspiring them.

"Our favorite team is the Americans!" one young swimmer said.

"The Americans are very good!" said another in a pool.

And staffers remember Ervin as the tattooed heavy metal guitarist who had a love for sharing the sport with the next generation.

"Go Tony. We're so proud of him. That's incredible," O'Melveny said. "To win an Olympic gold medal….We're happy to be a part of his story."