Swimming is one of those sports the bulk of Americans only pay attention to every four years.
But, every four years, it becomes one of the biggest and most talked about events of the Olympics.
The Tokyo 2020 Olympic Games will be no exception as Team USA looks to dominate in the pool once again.
But, San Diegans may want to pay extra close attention to the Tokyo 2020 countdown, because for the first time in decades, the city is filled with a bunch of Olympic caliber swimmers all training for a chance to hear their national anthem and get a medal placed around their neck.
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"The deal is, if you make the U.S. Olympic team, you're a medal candidate," said David Marsh, the 2016 Rio Olympics women's coach.
Marsh is the reason why heading into Tokyo, San Diego has its largest collection of Olympic hopefuls in the pool... maybe ever.
After decades on the east coast, Marsh and his wife moved to San Diego in 2017 to form a professional swim club called "Team Elite Aquatics."
Marsh said his kids were all out of the house and the timing just seemed right for a new adventure. But, it's also something he had thought about for years.
He would often visit the U.S. Olympic Training Center in Chula Vista (now the Elite Athlete Training Center) for short camps with teams and wonder why more elite swimming groups weren't based out of the area.
"This is an amazing atmosphere, climate, healthy culture, triathlon background. The open water swimming that goes on for so many master swimmers in town, this is such a healthy culture for swimming," said Marsh. "This is the ideal place for professional swimming."
Marsh earned his reputation as one of America's great swim coaches during a dominating 16-year run at Auburn University. He was named National Coach Of The Year eight times.
He left the university in 2007 to become the CEO & Director of Coaching for SwimMAC, an elite club based out of Charlotte, North Carolina.
In 2016, his club placed more swimmers on the U.S. Olympic team than any other program.
In fact, if Team Elite were a country, Marsh said they would have placed 3rd in the 2016 Rio Olympics swimming medal standings.
"So I hope the same thing happens here that happened in Charlotte, where we became the number one city for producing Olympians for the USA in swimming," he said.
A number of high profile swimmers followed him to San Diego including 2016 Rio gold and silver medalist Kathleen Baker.
He has 18 professional swimmers in his group, about half of whom are trying to make the Olympics for Team USA and the other half for other countries including Mexico and Israel.
Kendyl Stewart, a Carlsbad native who broke records at the University of Southern California and narrowly missed making the Olympics four years ago, credits Marsh with reinvigorating her passion for swimming.
"To be here and be in this full-circle moment in my swimming career with world record holders and Olympic medalists and training to be one next summer, it's the weirdest thing," said Stewart who is back training at the same pool where she swam as a kid.
Team Elite practices at the Lawrence Family Jewish Community Center in La Jolla, but observers might be surprised at what a typical practice looks like.
More often than not, there's much more to the program than just swimming laps.
"I think Marsh is really known for his getting us in the water and using our bodies in different ways," said Jacob Pebley, a 2016 Olympian backstroker.
Marsh's creative training philosophy has already tapped into the things which make San Diego great.
He holds open water swims in the ocean, encourages his athletes to surf as much as possible, and invites members of the military's special warfare units to practices for unique sessions on breathing techniques and games of underwater torpedo.
"It's really about getting a level of exertion and effort that is unusual and breaks their mold a little bit and they find new capacities within themselves that they might be able to translate back to their swimming," said Marsh.
He also created an elite program for high school swimmers called the "Team Elite Sting Rays" and often intermingles the younger swimmers with his professional swimmers during practices.
"We'd like to make it not just about 2020, but 2024, and especially 2028 going into the LA Olympics," said Marsh.
San Diego has long been considered one of America's premier Olympic cities and now it may be on the verge of cementing the reputation in the pool as well.