She is perhaps the most dominant athlete of all time. With 34 Grand Slam titles (21 singles and 13 doubles) she is 4 major singles titles ahead of Roger Federer, who many consider the GOAT [greatest of all time]. However, the gap [in ranking points and prize money] between Serena Williams and the rest of the WTA is so vast that in any given tournament she competes in, it is always hers to lose.

What puts Serena light years ahead of her competition?

Like with all champions, there are many factors. There’s her physical prowess, her incredible shot making, her tactical mastery, her superior serve but even more importantly, her mental toughness.

The most noticeable advantage for Serena, visually, is her physique. When you look at her, she passes the “eye test” as many professional scouts have said. There are no other women on the tour that matches up with her, physically. With dynamically powerful legs, and a core made of steel, she is able to generate incredible power and spin. She han explosive first step that allows her to run down potential winners from her opponents. At 5’9’’, she is not as tall as Maria Sharapova, giving her a lower center of gravity, and superior dynamic balance. Her rare combination of power and flexibility allows her to hit a ball that put some men to shame.

Her ability to punish the ball is striking, but Serena also has hands like a magician. Her volleying skills are well documented by her 13 doubles Grand Slam victories. With a sublime combination of reflexes and deft touch, Serena displays the finesse of an artist around the net.

As she has matured, Serena has also developed a mystifying ability to create short angle shots that run her opponent off the court. This forces her opponents to come up with a shot nothing short of spectacular to avoid being in a lot of trouble after the return.

Power, speed and touch are important elements of a great game but without a solid strategic foundation, many of these skills would be neutralized by a player with superior tactics. Serena plays tennis like a chess master. Intuitively, she knows where to position herself on the court throughout a point to put her in the best spot to emerge victorious. Like a tiger stalking it’s prey, Serena knows how to set up her opponents, exhaust them completely, and go for the kill.

Serena Williams serve broken down by ESPN Sports Science.

Serena’s biggest technical advantage is her serve, which is widely regarded as the most important shot in tennis. Serena’s motion is rhythmic, fluid, and extremely well coordinated. Comparing the serves of the other top women in the game, Serena has one decided advantage. She uses her hips, seamlessly, into and out of the stroke. Like Federer and many of the other great servers, Serena rotates her hips away from the court as she goes into her toss, and once she hits her maximum stretch, her hips immediately and seamlessly rotate towards the court, creating a spiraling effect that magnifies the power of the shot. It is similar to tightening a coil and then, releasing it. Many other women use their legs well but this corkscrew-like effect is what separates Serena from the pack. The result is effortless power, with a connection to the stroke that is not present in the other women.

In comparison, Sharapova, Kvitova, Halep, Bouchard, and Ivanovic all lack this one critical element to the serve. Their serves resemble more of a squat and thrust action that is relatively inefficient. The result is inconsistent timing and over-rotation, which creates a consistently changing contact point. This is why Serena continues to dominate, while the other women struggle to hold their serve.

Finally, Serena is the fiercest competitor the WTA has ever seen. All you have to do is look at her long list of comeback wins to know that she has the heart of a lion with ultimate belief in herself. In fact, it was previously illustrated by FiveThirtyEight that she only gets better as a tournament progresses.

At the Australian 2003, she was down 1–5 to Kim Clijsters in the 3rd set of the semi-finals and went on to win.

Then there was 2005, when she stunned Sharapova by saving 3 match points in the semi-finals of the Australian Open to win the match.

In the finals of the same tournament, she went from being blown off the court by Davenport in the first set, to ultimately winning the tournament.

At Miami in 2007, she had just lost the first set 0–6 to Justine Henin, and was down double match point, and came back to win the title.

In this year’s semi finals of Roland Garros, despite battling illness, Williams came back from a set down to trounce Timea Bacsinszky.

Finally, she has survived all three of her battles with Vika Azarenka this year, including most recently at Wimbledon.