She gets better with age

Tennis is supposed to be a young woman's game (in relative terms), yet Serena Williams continues to defy the odds.

In 2013, Serena, then 31, became the oldest women's tennis player to be ranked No. 1 since the computer rankings began in 1975. Now 33, Serena Williams has become more and more dominant as time marches on.

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She's the Grand Slam queen

In her career, Serena Williams has won the fifth-most Grand Slam titles with 36. Her 21 individual majors place her only one behind Steffi Graf's Open-era record. Serena and her sister Venus Williams also are an undefeated 13-0 in Grand Slam doubles championship matches.

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There's a Slam named after her

The 'Serena Slam' became popularized in 2002-2003 when Williams won four Grand Slam tournaments in a row. With Serena's 2015 Wimbledon victory, she accomplished the feat for the second time in her career. (Photo: Getty Images)

She's made more money than any other women's tennis player

Throughout her illustrious career, Serena Williams has made over $72 million in on-the-court earnings. That total is more than double the second-highest active earner on the tour, Maria Sharapova.

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She's the best tennis player in the world

Not to make too bold of a statement, but Serena Williams is the best active tennis player, male or female. Williams holds the most major singles, doubles and mixed-doubles titles combined among active tennis players.

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She likes to be No. 1

Serena Williams has been named the top-ranked player in WTA six times in her career. She first earned the No. 1 world ranking in 2002. And eleven years later, she earned that spot for the sixth time.

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Her serves are pretty fast

Serena Williams's 128.6 mph serve at the 2013 Australian Open is the third-fastest serve ever on the WTA. The blistering serve was topped by her sister Venus (129 mph) and Sabine Lisicki (131 mph).

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She's the first to ever win six titles at 3 majors

Williams was not only the oldest woman to ever win a major, but also the first to win a half-dozen titles at three different Grand Slam tournaments. She's also won the Australian Open and U.S. Open six times each.

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She almost won a pure Grand Slam

Although she's accomplished the Serena Slam twice in her career, Williams hasn't won the pure Grand Slam (winning all four majors in the same calendar year) ... yet.

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She's the first African-American woman to win a major since 1958

After winning the 1999 U.S. Open, Serena Williams became the first African-American woman to win a Grand Slam tournament since Althea Gibson in 1958.

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She's a four-time Olympic gold medalist

Serena Williams is a four-time Olympic gold medalist. Serena and her sister have won the gold medal three times as doubles partners (2000, 2008, 2012). Serena won her first individual gold at the 2012 Summer Olympics.

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She's business savvy

Serena has built quite the post-tennis career once she decides to hang up the racket. According to Forbes, Williams pockets $13 million in endorsements per year, which is more than what she makes on the court. Williams also is a part owner of the NFL's Miami Dolphins.

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She won 26 straight U.S. Open matches

Before being upset in the 2015 U.S. Open semifinals, she won a ridiculous 26 consecutive matches. Prior to losing this year, her last loss in the major was in the 2011 finals.

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Her sister is pretty good, too

Fifteen months older than Serena, Venus Williams is a teammate and opponent to her sister on the tennis court. The sisters have won three Olympic gold medals together along with 13 grand slam tournaments. Serena leads the sisterly head-to-head series 15 to 11.

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