Why Does Serena Williams Dominate Top Players but Struggle with Unknowns?

Serena Williams has struggled through most of her matches at the 2015 BNP Paribas Open at Indian Wells, even though she has yet to play anybody ranked inside the Top 25.  

Williams' next opponent will be No. 3 Simona Halep in the semifinals. Cakewalk.

Unlike most players, Williams has a tougher time against lower-ranked players than those ranked in the Top 10. Williams is more susceptible to an upset in early rounds against players she has never faced. 

She dominates top players. 

Williams' record against the current Top 10 is 62-6. Four of those players have never beaten Williams. Only Sharapova, who is on a 17-match losing streak, has more than one win against Williams. She won two in 2004. 

Novak Djokovic has lost to Roger Federer 17 times. That's more career losses against one Top 10 player than Williams has against the entire Top 15. 

Yet in 2014, Williams lost to Alize Cornet three times. Her career record against Cornet is 3-3.

Historically, Williams loses to players she has little history with. She lost to tiny Tiantian Sun in 2005 in Beijing. Sun, ranked No. 128, beat Williams in straight sets in their only meeting. Williams famously lost to Virginie Razzano in the first round of the 2012 French Open. It remains the only time Williams has lost in the first round of a Grand Slam. 

Last year, Williams suffered early-round upsets to Garbine Muguruza (No. 35) at the French Open and Jana Cepelova (No. 78) in Charleston. It was her first meeting against Cepelova and the second against Muguruza.

In 2004, Williams lost to Alina Jidkova in Linz. Now retired, Jidkova, who was ranked No. 73 at the time, told USA Today that people are skeptical when she tells them she beat Williams. 

"It was the biggest win of my career...When I tell people they don't believe me, I think. They always ask, 'Really?'And the next thing is, 'But you are so small and skinny.'"

Meanwhile, Williams is on a 17-match, decade-long winning streak against Sharapova, winner of five Grand Slams.

Because the Williams vs. Sharapova rivalry includes the biggest names in women's tennis, it's sometimes over-analyzed. Williams' record against Sharapova is similar to her record against most top players, including Hall of Famers.

She has a 10-4 record against Lindsay Davenport. 

Only five players have beaten Williams more than four times. They are Venus Williams (11-14), Jennifer Capriati (7-10), Martina Hingis (6-7), Justine Henin (6-8) and Elena Dementieva (5-7). None have a winning record against Williams.  

So why does Williams demolish top players and performs poorly against unknown opponents? 

The dominance against top players has more to do with Williams' ability to pick apart a player's tendencies. Williams is a student of the game. She likes to study an opponent before she can dissect them and ultimately destroy them.

The more she plays an opponent, the more information she gathers. She's had more opportunities to figure Sharapova out. 

When faced with the unknown or worse, the unusual, Williams needs time to adjust. In her 7-5, 7-5 win over Monica Niculescu, Williams struggled to find her rhythm. She made 48 unforced errors.

Niculescu hit junk balls with heavy slice. She frustrated Williams. 

It's not like Williams was unaware of Niculescu's style of play. As she told reporters in her post-match press conference.

"I know her game.  I think everyone in the locker room knows her game. But, boy, she was interesting...I just wasn't able to get my rhythm today.  I'm just glad to get through that match.  It was definitely a super tricky match for me."

Players who are unfamiliar or who throw an unorthodox game at Williams, seem to have the most success against her.

Against Cornet at Wimbledon in 2014, Williams allowed the match to get away from her. Cornet, like Niculescu, used slice to take the pace off the ball.

Bewildered by the loss, Williams told reporters “I think this defeat is important to study...Right now I don't really know what I did wrong. Usually I do. Usually I know I did this, this, and that. I have a few ideas, but this will be a really good one for me to kind of like assess and figure out what I can do to do better next time."

A perpetual learner, Williams corrects wrongs before, during and after the match. She seems to suffer emotionally when she makes the same error more than once. Agony in her face, Williams often appears distraught until she figures things out. 

She unearths Plan B, as she did against Niculescu. She explained in her press conference, "I just said, 'You're not going to lose this match. You have to figure out a way to win it.'" 

Sharapova tried to mix things up against  Williams in the 2015 Australian Open final. She won two points off Williams, using the drop shot. Williams smacked a third attempt into a winner. Sharapova tucked her drop shot away. 

Williams' coach, Patrick Mouratoglou, understands her thought process perhaps better than anyone outside of her family. In an interview with Mark Hodgkinson for BT Sport, Mouratoglou talked about how Williams continues to work on her game. 

Serena always wants to improve. She is never satisfied and wants to become better every day. That is the difference between the good players and the champions. It is a very good thing. This tennis world is constantly changing. What is true today may be wrong tomorrow. If you don’t make progress, others will and you will be overtaken.

She has taken over the WTA Tour. Beating Top 10 players is routine. It's the players who have yet to make her acquaintance that she has to worry about.