The 7 highest-paid tennis players

To many, tennis is a leisurely pastime, but for the most talented professional players in the game, it's a way to nab lucrative paychecks. From hefty tournament winnings to enormous endorsement contracts, some of the top tennis players are winning on and off the court.

Learn more about the highest-paid tennis players and how much they're earning by staying at the top of their game.

Kei Nishikori Net Worth: $9 Million

Japan's top pro tennis player, Kei Nishikori, made a men's Grand Slam final in 2014 — the first Asian man to accomplish the feat. Ranked No. 6 in the world by the Association of Tennis Professionals (ATP), he'll compete on Japan's national tennis team for the third time at the Rio Olympics.

Although Celebrity Net Worth puts Nishikori's net worth at $9 million, Forbes puts his earnings at $33.5 million. That amount includes $3.5 million in winnings and $30 million in endorsements from 15 sponsors, with a renewed Uniqlo deal valued at eight figures per year. As of June 2016, Nishikori's career earnings totaled $13.3 million.

Andy Murray Net Worth: $70 Million

Andy Murray is the No. 2 tennis player in the world, according to the ATP. In 2013, he made history as the first male Brit since 1936 to win Wimbledon. This year, he has already won three highly-coveted titles at Wimbledon, The Queen's Club and the ATP World Tour Masters 1000 in Rome. The two-time Olympic medalist will also represent Great Britain in Rio.

As one of the highest-paid tennis players in the game, Murray has garnered a total of $46.7 million in career earnings. In the past year, he's earned $8 million in prize money and $15 million in endorsements. With deals with Standard Life, Head and Rado, plus a four-year contract with Under Armour worth $6 million annually, Murray's net worth is estimated at $70 million.

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Rafael Nadal Net Worth: $140 Million

After missing the French Open due to a wrist injury and withdrawing from Wimbledon, Rafael Nadal is headed to Rio in pursuit of a gold medal as part of Spain's Olympic tennis team. The famed tennis player previously won a gold medal in men's singles at the Beijing Games in 2008. Other career highlights include winning the ATP World Tour Masters 1000 in Madrid and the U.S. Open in 2013.

Nadal's career earnings total $78.2 million, making him one of the highest-paid tennis players in history. Forbes puts his earnings at $37.5 million, including $5.5 million in winnings and $32 million in endorsements off sponsors like Nike, Tommy Hilfiger and Kia Motors. His net worth is estimated at $140 million.

Novak Djokovic Net Worth: $160 Million

Novak Djokovic has been ranked the top tennis player in the world since February 2015. In addition to becoming the first Serbian tennis player to win a Grand Slam singles title, Djokovic earned the honor of holding all four major championship titles after winning the French Open in 2016. He's slated to compete as part of the Serbian team in the 2016 Olympics.

In 2015, he became the first tennis player in history to earn $20 million in prize money during one season, according to Forbes, and he's now ranked by the ATP as the highest-paid tennis player in terms of career earnings, amassing a total of $101.9 million. Endorsements from Uniqlo, Head, ANZ, Peugeot and Seiko brought in $34 million between June 2015 and June 2016, reported Forbes.

Serena Williams Net Worth: $160 Million

Forbes ranks Serena Williams as the world's highest-paid female athlete. Her earnings total $28.9 million, including $8.9 million in prize money and $20 million in endorsements from more than a dozen sponsors, including Nike, Delta Airlines and IBM.

Currently ranked No. 1 in singles, she's won over $74 million in total prize money, according to December 2015 estimates from the WTA Media Information System. A four-time Olympic gold medalist, Williams joins Team USA for the Rio Olympics.

Andre Agassi Net Worth: $175 Million

Although now retired, Andre Agassi was ranked No. 1 in the world at the peak of his career. Before hanging up his racket, he won a career Grand Slam and recorded $31.2 million in career earnings.

By 2004, Forbes estimated Agassi had earned $200 million off endorsements, just two years before he retired. His net worth today is estimated at $175 million.

Learn: 3 Steps to Avoid Running Out of Money in Retirement

Roger Federer Net Worth: $350 Million

In 1998, Roger Federer won the Wimbledon junior men's singles title, and in 2009, he earned the highly-coveted career Grand Slam. He's out of commission for the season due to injuries, which will keep him on the bench for the Rio Olympics, but he intends to make a comeback.

Federer's net worth is $350 million, including $60 to $70 million in earnings per year, reported Celebrity Net Worth. Since going pro 18 years ago, Forbes cites his total career earnings at $98 million and lists his 2015-2016 endorsement earnings at $60 million, with Nike, Mercedes-Benz, Rolex and Credit Suisse among his top sponsors.

Keep Reading: Highest-Paid Olympic Athletes, Like Michael Phelps

Career earnings are according to 2016 data from the Association for Tennis Professionals unless otherwise noted. Earnings from endorsement deals and winnings are according to data from Forbes' The World's Highest-Paid Celebrities list, which calculated earnings using data from June 2015 to June 2016. Net worth figures are indicative of assets versus liabilities and according to CelebrityNetWorth.com.

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