Serena Williams: The 5 Biggest Threats to Her Dominance in 2014

David ReplogleContributor IIINovember 4, 2013

ISTANBUL, TURKEY - OCTOBER 27:  Serena Williams of the United States is prsented the Billy Jean King Trophy after defeating Na Li of China during the final of the TEB BNP Paribas WTA Championships at the Sinan Erdem Dome on October 27, 2013 in Istanbul, Turkey.  (Photo by Matthew Stockman/Getty Images)
Matthew Stockman/Getty Images

Serena Williams' 2013 season will go down as one of the most stunning in tennis history. The American finished as the world's top player for the third time, compiling a 78-4 record replete with two Grand Slam titles and nine other Tour-level crowns. Along the way, she battled illness, a few injuries and fatigue—yet still managed to play more, and win more, than at any other point in her career.

As we turn the corner into 2014, Serena's on the verge of rewriting history yet again—she could easily pass Chris Evert and Martina Navratilova's joint mark of 18 Grand Slam titles. Who could possibly impede the American's dominance? Here are five likely contenders.

ISTANBUL, TURKEY - OCTOBER 22:  Victoria Azarenka of Belarus celebrates a point against Sara Errani of Italy during day one of the TEB BNP Paribas WTA Championships at the Sinan Erdem Dome on October 22, 2013 in Istanbul, Turkey.  (Photo by Matthew Stockm
Matthew Stockman/Getty Images

1. Victoria Azarenka (2013 Year End Ranking: #2)

Serena's record against her fellow Top 10 opposition this year was a dazzling 21-2—but those losses both came at the hands of none other than Azarenka.

Vika toppled Serena in the finals of the Qatar Total Open in February, and edged her again in the championship match of the U.S. Open warm-up tournament in Cincinnati. Both wins were on hardcourts — the Belarusian's preferred surface—and both were incredibly tight three-set affairs, proof that Vika can stay with Serena mentally in ways that most other Women's Tennis Association players cannot. This year's U.S. Open final was further proof of that. Despite losing the match in the third set, Azarenka shocked many by even extending the match that far—at one point, she'd been down a set and two breaks against Williams' superior serve. For many, that's a death knell; for Vika, that's a challenge.

Azarenka spars toe-to-toe with Williams on the baseline, matching powerful groundies stroke-for-stroke. She also reads Serena's serve better than anyone, pouncing on big bombs with trademark pinpoint accuracy. In order for Vika to continue to challenge Serena this coming year, she needs to do two things: fix her ineffective second serve and stay healthy. Injuries—and double faults—plagued the World No. 2 for the majority of this season. 

ISTANBUL, TURKEY - OCTOBER 27:  Na Li of China returns a shot to Serena Williams of the United States during the final of the TEB BNP Paribas WTA Championships at the Sinan Erdem Dome on October 27, 2013 in Istanbul, Turkey.  (Photo by Matthew Stockman/Ge
Matthew Stockman/Getty Images

2. Na Li (2013 Year End Ranking: #3)

The Chinese superstar captured just one lone title in 2013—at a minor tournament in her home country—yet had the most consistent season of her life at a mature 31 years of age. 

By hiring Carlos Rodriguez, the man who brought Justine Henin's career to remarkable heights, Li sent a big message: that she wasn't content staying a rung below the WTA's "Big Three," also known as Serena, Sharapova and Azarenka. The Chinese has one major title to her credit (the 2011 French Open), yet her results in the Slams have been scattershot since then. Rodriguez, she hoped, would restore some order to the chaos.

He did exactly that—mainly through dragging Li through an ultra-strenuous training regimen. A fascinating New York Times magazine article from the summer details just how intensely Li rededicated herself to her fitness, digging in for agility workouts, beach volleyball and vicious cycling sessions. A second Grand Slam championship almost materialized as a result. 

Perhaps the most telling match of the year for Li, however, was her last. In the finals of the WTA Championships, after going undefeated in her four previous matches, she came up against Serena in the final. For a set-and-a-half, the Chinese played lights-out tennis. Then she faded, and Serena—per usual—picked up her level. The American triumphed 6-0 in the third. In 2014, can Li keep it up for an entire match? 

NEW HAVEN, CT - AUGUST 24:  Simona Halep of Romania answers questions during a press conference after the Women's Final on Day Seven of the New Haven Open at Yale at the Connecticut Tennis Center on August 24, 2013 in New Haven, Connecticut. Halep defeate
Elsa/Getty Images

3. Simona Halep (2013 Year End Ranking: #11)

When a tennis player wins six titles in a year, usually people know about it. Not so in the case of young Romanian Simona Halep, who quietly compiled one of the most incredible breakthrough seasons in recent memory. Too bad not many tennis outsiders were aware of her triumphs.

One reason why Halep was so under the radar for all of 2013, even while winning so often, was because her Grand Slam results lagged—she didn't move past the fourth round in any of the big four tournaments. The 22-year-old also failed to make much of an impression against Williams: In two matches vs. the American, Halep garnered just seven games.

That being said, Halep certainly has the game to trouble Williams this coming year—think the athleticism and stroke production of Kim Clijsters mixed with the precision of Martina Hingis. She'll also be heading into 2014 on a high, sweeping her last two tournaments of the year with wins over Ana Ivanovic, Sam Stosur (twice) and Nastya Pavlyuchenkova (twice) and finishing on the cusp of the Top 10 rankings. 

TOKYO, JAPAN - SEPTEMBER 26:  Eugenie Bouchard of Canada in action during her women's singles quarter final match against Venus Williams of the United States during day five of the Toray Pan Pacific Open at Ariake Colosseum on September 26, 2013 in Tokyo,
Koji Watanabe/Getty Images

4. Eugenie Bouchard (2013 Year End Ranking: #32)

The WTA has been eager—even desperate—for the next generation of young stars to make their marks on the pro game, and in 2013 they made some big, big strides. Along with fellow youngsters like Halep, Sloane Stephens and Monica Puig, 19-year-old Canadian phenom Eugenie "Genie" Bouchard broke through with a stellar campaign.

Tall, strong, armed with huge groundies and an all-court game (she's been working with former Top 10 net rusher Nathalie Tauziat as of late), Bouchard showed many of the game's elite just how big a threat she could pose. Besides scoring wins over Jelena Jankovic, Ivanovic and Stosur, she brought the likes of Angelique Kerber, Venus Williams and yes, even Serena Williams to three sets along the course of the year. 

Bouchard's confidence grew more and more as 2013 progressed. To make that next big stride, she needs to harness that confidence and translate it into wins against the best players on the biggest stages.

LONDON, ENGLAND - JULY 01:  Serena Williams of United States of America looks dejected during her Ladies' Singles fourth round match against Sabine Lisicki of Germany on day seven of the Wimbledon Lawn Tennis Championships at the All England Lawn Tennis a
Mike Hewitt/Getty Images

5. Serena Williams

Serena has said it many times before, and usually all of us fans just nod our heads and agree: Most often, Williams' biggest enemy is staring her down in the mirror.

Usually nerves play a big factor in the American "beating herself"—look no further than the fourth round of this year's Wimbledon. While Sabine Lisicki did play a stupendous match under pressure, it was also one that Serena should never have lost—or given away, rather. Fresh off a cathartic win at the French Open and riding the longest win streak of her life, Williams battled from a set down against her German opponent to find herself up 3-0 in the third. Then, nerves took hold—and refused to let go. Serena's shots started landing short and spraying wide, and Lisicki capitalized. She upset Williams 8-6 in that crucial decisive set.

With the pressure on to break—or at least equal—the 18 Grand Slam record mark held by all-time greats Evert and Navratilova, will there be any more self-inflicted losses during the 2014 Grand Slam season?

Serena—both Serenas—certainly hope not.