If you want to make millions out of a sporting career, your best bet might be to take up golf...
There are already 143 men who have won at least $1 million in prize money this year on golf's PGA Tour in the US and the European Tour. Justin Thomas, pictured, tops the money list for 2017 with $9.9 million from 25 events.
By contrast, 49 men have won at least $1 million on tennis' ATP World Tour this season. Reigning French Open and US Open champion Rafael Nadal leads the money list with $12.6 million in on-court earnings
Although Roger Federer has won 19 tennis majors compared with 14 golf majors for Woods, the two have earned roughly the same prize money in their careers with around $110 million.
These numbers change when we compare women's tennis and golf. With the women's tennis season now officially over, 37 players on the WTA tour -- including year-end world No. 1 Simona Halep -- made $1 million or more.
Venus Williams topped the 2017 money list in women's tennis, earning $5.5 million from reaching two major finals at Wimbledon and the Australian Open and finishing runner-up at the year-end WTA Finals.
South Korean golfer Sung Hyun Park, winner of the Women's US Open, leads the LPGA 2017 money list with $2.3 million in prize money.
With a sport so dependent on physical strength, endurance and recovery, tennis players have a limited window in their careers during which they have to make their money.