Pro poker player wins extra $310,000 away from the table

What's better than winning $239,000 in a poker tournament? Winning an extra $310,000 from your friends at the same time.

World Series of Poker
Source: Courtesy WSOP

That's what pro poker player Brian Hastings did. Last weekend, he took the $10,000-buy-in, 7-card stud event at the World Series of Poker for that nice first-place payout, and he laid claim to the gold bracelet awarded to tournament winners.

But even more lucrative was the money he won on side bets. Such bets are common in the pro poker world, but they're not often talked about.

Hastings explained to CNBC how his recent sidebets worked: Before the summer started, he wanted to make a wager that he would win a bracelet at some point during the 68-event World Series. His buddy Jason Mercier, another top pro, took him up on the bet and gave him 3.3-to-1 odds. Hastings bet $50,000 on himself. Now Mercier owes him $165,000.

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But that's not all—he did another set of side bets specifically on the recent tournament. The wagers were in three parts. Against Mercier, for instance, Hastings won $10,000 for "making the money" (the top 16 of 91 entrants), another $10,000 for making the Final Table (top 8) and another $10,000 for winning. If neither Hastings nor Mercier had made the money, or if they both had, those parts of the bet would have been a wash.

A variety of similar bets against other pros netted Hastings about $116,000 more, for a total of $311,000.

Live trading with a poker pro
Live trading with a poker pro   

Such side bets are actually quite common in the rarefied world of professional poker. Last year, pro competitor Daniel Negreanu teamed with fellow pro Phil Ivey, the two of them taking all comers in even money in a bracelet bet. Ivey won for the two men. In 2010, Tom Dwan had a huge number of bracelet bets, rumored to have been worth several million if he had won. He didn't. He did finish second in a tournament, however, which made a lot of players very nervous for a while.

One may be tempted to ask why poker pros add so much risk to what could already be an expensive summer if they encounter too much "negative variance"—the poker term for bad luck.

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Hastings told CNBC that he "learned a lot over the past year, think others underrate my skill." He added that he's "in a great place in life right now, in a great 6-month relationship, and thought I was prepared to play my A-game every day for 7 weeks straight."

That decision has obviously paid off. So did another decision he made long ago. In 2008, when he was still 19, Hastings posted in an online poker forum that he was "totally lost" in 7-card stud and asked for a book recommendation to help him learn. He bought a book, studied the game and practiced online.

He has turned the investment in that book, and his own self-confidence, into nearly $550,000.