Eric Byrnes’ Let Them Play Foundation has taken the former Diamondback through some adventurous roads.

So far, he’s swam with fish, raced some mascots and biked through northern California.

He’s just getting started.

On July 22, Byrnes began his Triathlon Across America by jumping into McCovey Cove behind AT&T Park, the Giants’ home field, and swimming seven miles across the bay to Oakland.

Awesome to have my large fish friend come support the @LTPFoundation #TriAcrossAmerica 7 mile SF to Oakland swim 🏊‍♂️🦈 pic.twitter.com/EroLJGN7KI — Eric Byrnes (@byrnes22) July 27, 2018

He found some company, tweeting a video from above of a giant fish swimming near him.

It was the beginning of Byrnes’ race across the United States. He will be biking 2,344 miles from San Francisco to Chicago, making several stops along the the way. When he arrives on Aug. 15, he’ll ditch the bike and lace up his running shoes.

Byrnes will run 846 miles from Chicago to New York City. He plans to arrive Sept. 15.

But before he started his course, he made a pit stop at the Oakland Coliseum, where the A’s play, for some training.

He raced against the A’s historical mascots in the style of Freeze of the Braves. The mascots got a head start before Byrnes bolted out.

Byrnes’ organization, the Let Them Play Foundation, encourages kids to participate in physical education and after school programs. According to his website, the money raised during his journey will be donated to his foundation.

He is planning to recruit other swimmers, bikers and runners to join as he travels.

The former baseball player has remained active since retiring. He has completed 11 Ironman races, 20 ultra marathons and set the world record for most holes of golf played without a cart. His 245 holes of speed golf in April raised money for non-toxic treatments for lymphoma.

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