Bettors weren't looking Phil Mickelson's way before the PGA Championship started, even at 200-to-1 odds.
By Sunday he was BetMGM's biggest liability, and the house paid out a lot of winning tickets.
Mickelson became the oldest player to ever win a major, taking home the PGA Championship by maintaining a lead despite tough conditions that led to many high scores. Not many saw that coming a few days ago.
Before the tournament, when 50-year-old Mickelson was +20000 at BetMGM, only 0.8 percent of tickets and 0.5 percent of the money was on him to win it all. That's an amazing win for those few bettors.
Mickelson's odds kept dropping as he surged to the lead, and by Sunday he was down to +300. That was still an enticing price for the tournament leader — Brooks Koepka was the favorite at +160, with plenty of skepticism that Mickelson could keep the lead — and bettors kept taking Mickelson. Before Sunday's final round teed off, 6.5 percent of the money bet on the tournament winner was on Mickelson. That was tied for the second-highest figure, and a lot of the bets were at good odds. That ended up costing BetMGM.
Most Mickelson backers probably regretted not putting a few bucks on him earlier in the week, but the historic win was still profitable for bettors.
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