The 5 highest-paid golfers in the world 

Today, the 100th PGA Championship kicked off in St. Louis, Missouri. Some of the most talented golfers in the world will compete for their share of $10.5 million in purse money, and the winner will take home $1.89 million.

The world's richest golfers are not only fighting for prize money, they are also competing for lucrative sponsorship and endorsement deals which can make them incredibly wealthy. According to Forbes, five of 100 highest-paid athletes in the world are golfers, and four of them are from the United States.

Here are the five highest-paid golfers in the world:

Pay: $26 M

Salary/winnings: $21 M

Endorsements: $5 M

Country: United States of America

Pay: $37.7 M

Salary/winnings: $3.7 M

Endorsements: $34 M

Country: Northern Ireland

Pay: $41.2 M

Salary/winnings: $11.2 M

Endorsements: $30 M

Country: United States of America

Pay: $41.3 M

Salary/winnings: $4.3 M

Endorsements: $37 M

Country: United States of America

Pay: $43.3 M

Salary/winnings: $1.3 M

Endorsements: $42 M

Country: United States of America

Despite being raked 51st in the world golf rankings, Tiger Woods remains the highest-paid golfer in the world. But Woods didn't make this fortune by winning titles, he earned it through endorsement deals with companies like Nike, Monster Energy and Bridgestone. According to Forbes, Woods made $43.3 million last year, and has made $1.5 billion since turning pro in 1996, but less than 10 percent of these earnings came from prize money.

In 2017, Bridgestone Golf's then-CEO Angel Ilagan told CNBC that Woods "actually has more power as an endorser than he does as a player."

Close behind Woods is Phil Mickelson, who reportedly raked in $41.3 million in 2017. Mickelson, who is 48-years-old, and Woods, who is 42-years-old, are the two oldest athletes on Forbes' list of the 100 highest-paid athletes.

Jordan Spieth is the third highest-paid golfer in the world. The 25-year-old golfer has some significant sponsorship deals himself with companies like Under Armour, Coca-Cola and Rolex.

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