It goes without saying that tennis can be a very lucrative sport, particularly for those who manage to stay at the top of the game for a considerable length of time.
Of the many legends that have thrilled us on court over the years, though, just who is the richest?
Now, per sportskhabri.com, the answer has been revealed, so read on for a breakdown of the top 10 wealthiest tennis players of all time.
10. Venus Williams - $95 million
Although she has not quite had the longevity of her sister Serena, Venus is still a seven-time Grand Slam winner, who has earned $46.5 million in prize money. A series of other highly successful partnerships and ventures see the 40-year-old crack the top 10 of this list.
9. John McEnroe - $100 million
Despite playing in an era where prize money was nothing compared to what it is today, McEnroe has still managed to parlay his legendary name into some serious cash. The 62-year-old has worked on a variety of projects over the years - and is a regular commentator on the sport to this day.
8. Maria Sharapova - $135 million
She may only have won five Grand Slam titles, but Maria Sharapova was a firm favourite with brands when it came to endorsements during her career. Her success is proven by the fact she came top of the Forbes Richest Female Athlete List every year from 2006-2016.
7. Pete Sampras - $150 million
The legendary American had an exceptional career, lifting 14 Grand Slam titles. Although he was not as in-demand as some of the other names on this list when it came to endorsements, Sampras still pocketed a tidy sum during his playing days.
6. Andy Murray - $165 million
Injuries have not been kind to the 34-year-old Brit, who would undoubtedly have won more than his three Grand Slam titles had he had better luck fitness-wise. Still, Murray has managed to do very well for himself in spite of his injury woes. $61.5 million in career prize money - backed up by over $100 million in sponsorship and endorsement income - is far from shabby.
5. Andre Agassi - $175 million
The big brands could not get enough of Agassi during his playing days. Adidas, Nike, Ebel Swiss Watches and American Express were just some of the many companies that paid huge money to work with Agassi during the 1990's. The American was no slouch on the court either, completing a full set of Grand Slam triumphs.
4. Rafael Nadal - $190 million
Co-holder of the record for the most men's Grand Slam victories in history with 20, the 34-year-old Spaniard might well be higher on this list if it were not for injuries in recent years. Nadal has still earned an eye-watering $121 million in career prize money, helped by having won the French Open no less than 14 times! Brands like Nike and Tommy Hilfiger have also paid 'The Raging Bull' over the years from his association with them.
3. Serena Williams - $200 million
Serena Williams holds more Grand Slam titles than anyone on this list (23). The 39-year-old American is rightly regarded as the greatest female player of all time - and has the bank balance to back it up. Serena has earned an estimated $93.5 million on the court, but has also been in great demand off it as well. Endorsements deals with IBM, Beats By Dre, Aston Martin and others have netted her well in excess of nine figures during her career.
2. Novak Djokovic - $220 million
The 34-year-old Serbian has triumphed on no less than 18 occasions on the Grand Slam stage, with prize money accounting for the majority of his net worth. His association with companies such as Raiffeisen Bank International, Adidas and Bombadier Aerospace has also helped to swell his coffers.
1. Roger Federer - $900 million
We had to double-check this one, but it's accurate! The 39-year-old won his first Grand Slam in 2003 (when he was victorious at Wimbledon) and has never looked back. Federer has won a staggering 103 tournaments in his illustrious career - including a record-equalling 20 Grand Slam titles.
However, it is off the court where Federer has really raked in the cash. Estimated to have earned $770 million from outside deals with the likes of Rolex, Mercedes and Moet over the last two decades, the Swiss superstar is well clear of his peers in the net worth stakes.