Golf's winners are not always the top earners

Phil Mickelson might have pocketed £945,000 ($1.44 million) in prize money for winning golf's British Open Championship this weekend, but one expert told CNBC he has some way to go to catch up with golf's top earner.

Mickelson's latest victory makes him golf's second highest earner, with career earnings totalling at $190 million, according to Wealth-X, which researches ultra-high net worth individuals.

In contrast, Tiger Woods – who has not won a title in the past 17 major tournaments he has played in – is worth a staggering $590 million.

Wealth-X President David Friedman told CNBC that net worth goes way beyond winnings.

"It's the endorsements. Those are the key drivers of wealth," he said.

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Wood's sponsors include top names such as EA Sports, NetJets, Nike Golf, and Rolex, and he has just signed a new endorsement deal with Nike to replace a contract set to expire this year, according to ESPN.

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Mickelson also has some big sponsors including Barlcays, Callaway Golf, KMPG, and Rolex. That list is likely to grow after his latest win.

Friedman said some sponsors may see the British Open victory as a reason to back Mickelson.

"I think we'll see some migration to Phil in terms of social capital around the endorsements."

Mickelson is among the world's top earning athletes – worth just more than tennis player Roger Federer, at $180 million, but behind basketball player Kobe Bryant, who is worth around $220 million, according to Wealth-X.

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