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- Phil Mickelson racked up $100 million worth of losses gambling, according to a new book by Billy Walters.
- The golf star also tried to bet $400,000 on Team USA at the 2012 Ryder Cup, Walters wrote.
- "I would never undermine the integrity of the game," Mickelson said in response.
Phil Mickelson has bet over $1 billion over the past three decades, racked up $100 million worth of losses, and once considered placing a wager on Team USA winning the Ryder Cup, according to a new book.