A memoir has revealed new details about the suffocating gambling addiction suffered by pro golfer Phil Mickelson.

Mickelson risked over $1bn and lost nearly $100m

According to Gambler: Secrets from a Life at Risk by Billy Walters, from 2010-2014, Mickelson risked over $1bn and lost nearly $100m while gambling on sports. He averaged nine bets per day in 2011, bet $110,000 to win $100,000 a total of 1,115 times and bet $220,000 to win $200,000 858 times. Those wagers alone amount to over $311m in stakes.

Mickelson’s lavish and persistent betting behavior didn’t stop there. On June 22, 2011, he placed 43 bets on MLB games – a day when there were 15 games, meaning he bet an average of nearly three times on every game. That fateful day resulted in $143,500 in losses for the 45-time PGA Tour champion.?

Mickelson even called Walters in 2012 and asked him to wager $400,000 on the American team to win the Ryder Cup on his behalf. That is directly against the rules of not only golf but almost all professional sports.?Walters ultimately declined and scolded Mickelson.

Walters is considered the most successful American gambler ever. His claims in the book, which comes out on August 23, are from “two very reliable sources” and a collection of betting records.

“The only other person I know who surpassed that kind of volume is me,” Walters said in the book.

Mickelson’s gambling addiction has been documented in the past. In 2015, $3m was found to have been transferred from Mickelson to an intermediary of an illegal gambling ring. In a 2022 interview with Sports Illustrated, he called his gambling behavior “reckless” and “embarrassing” and said he had an “addiction.”

Mickelson said in June via social media that he hadn’t gambled in years.