James Adducci has doubled down. Golf Digest has learned that Adducci, the 39-year-old Wisconsin man who won $US1.19 million on Tiger Woods winning the Masters, has taken $US100,000 of his winnings and placed it on Woods to win the Grand Slam.

William Hill US confirmed the bet was placed overnight, Australian time, at the SLS Casino in Las Vegas, the same sportsbook where Adducci placed – and then cashed – his first bet. Michael Grodsky, William Hill’s vice-president of marketing, said Adducci flew to Vegas and placed the bet on Wednesday.

Adducci claims his initial $85,000 bet on Tiger to win the Masters at 14-1 was his first sports bet. The $100,000 bet at 100-1 odds on Tiger Woods winning the Grand Slam would net the 39-year-old Wisconsin man a $10 million payday. Tiger’s current odds of winning next week’s PGA Championship are listed at 8-1.

His first bet marked the largest payout on a futures ticket in William Hill’s US history. A $10-million payout would go down as one of the biggest in sports history.

“Tiger has history winning at Bethpage, and he won at Pebble, by the biggest margin in history,” Adducci told Golf Digest. “This is a very unique situation. That’s the way I’m thinking about it. We know that with every win, the energy level will get amped up. His game gets elevated. The expectation – does he play well under pressure? He’s the definition of excelling under pressure. That’s how my brain works.”

Though Tiger won what’s known as the “Tiger Slam”, holding all four Majors at the same time, nobody has replicated the impregnable quadrilateral clinched by Bobby Jones in 1930. Of course, at that time, Jones, the greatest amateur golfer ever, won the US Amateur and British Amateur to complete the Grand Slam, along with the US Open and Open Championship.

A USA Today report after William Hill’s celebration of his bet detailed Adducci’s criminal history, which includes four misdemeanour charges of domestic violence and 12 total guilty pleas.