It was Duhamel's second-biggest score after the 2008 Main Event win that earned him nearly $9 million and it brings his total live tournament earnings to $16.8 million.
“I feel incredible right now,” Duhamel said moments after the win.
“It doesn't get any better than that. It's the biggest buy-in of the summer and it's for charity, for One Drop, all those things combined it's an amazing day.
“It's probably my second-best day ever after the Main Event.”
Duhamel had a tough final table to overcome including fellow world champ Phil Hellmuth, winner of the inaugural $1m Big One for One Drop Dan Colman and online high-stakes legend Ben “Sauce123” Sulsky.
Duhamel Defeats Wealthy Philanthropist
To clinch the victory Duhamel defeated retired businessman Bill Klein heads-up.
Before retirement Klein was in manufacturing and owned a number of factories around the US.
Now Klein is known for pledging his poker winnings to charity.
Klein has appeared on High Stakes Poker and had a six-figure score in a WPT Super High Roller in 2012.
He took down almost $2.5 million, all of which he will donate to cancer research, having survived cancer himself.
“We all know Dan Colman is a great player but Bill (Klein) was playing pretty tough too,” said Duhamel.
“I didn't think he was going to play so well but he had some moves.”
Here are the full final-table payouts:
Medical Emergency Delays Colman Elimination
During Dan Colman's final all-in a spectator collapsed in the stands. The flop had been dealt as the emergency began and the tournament staff immediately stopped the hand mid-deal to call for a doctor.
A doctor was found in another ongoing event and CPR was performed on the elderly individual until paramedics arrived.
“It's so unfortunate and I hope that this guy is alright and I give all my thoughts and all my prayers to this guy and I really hope he's alright,” said Duhamel.
“I don't know what to say. The whole room didn't know what to do in that situation. It was really sad and we all hope he's going to be okay.
“For the rest, this is just a poker tournament and something like this puts it in perspective. It wasn't that important in the end compared to what happened in the end.
Click here for first-hand accounts of the incident.
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