Serena Williams went 78-4 with a career-high 11 titles in 2013. (Feng Li/Getty Images)
The Beyond The Baseline awards are our look back at the best -- and worst -- of the tennis season. Today we offer our final "grades" for the WTA Tour singles players. Serena Williams headlines the list after a dominant season in which she regained the No. 1 ranking. Click here for our complete archive of year-end awards.
Head of the class
Serena Williams: The 32-year-old didn't just cement her status at the top of the game; she systematically widened the gap between herself and the field. After winning two Grand Slam tournaments, including her first French Open since 2002, and collecting a career-high 11 titles overall while rolling up a 78-4 record and $12.4 million in prize money, Williams finished the year more than 5,000 points ahead of No. 2 Victoria Azarenka. (By comparison, Rafael Nadal finished fewer than 1,000 points ahead of No. 2 Novak Djokovic.)
Marion Bartoli: The Frenchwoman marched to the beat of a different drummer right to the end. Her run to the Wimbledon title wasn't the most difficult path we've seen -- No. 17 Sloane Stephens was her highest-ranked opponent -- but it was the feel-good story of the WTA season. Her quirky two-handed game, honed over the years by her father, finally paid off with her first major title as she coasted through the tournament and beat an overwhelmed Sabine Lisicki 6-1, 6-4 in the final. But the quirkiness didn't stop there. Less than six weeks later, after losing to Simona Halep on a secondary court in front of a sparse crowd at the Western & Southen Open in Mason, Ohio, Bartoli abruptly announced her retirement at age 28.
Li Na: Li, 31, had the most consistent season of her career, reaching the quarterfinals or better at 12 of 15 tournaments, including the final of the Australian Open and the WTA Championships and the semifinals of the U.S. Open for the first time. She moved up to a career-high No. 3, making her the highest-ranked Asian player ever. All that consistency and she's still tinkering with her game, buying into coach Carlos Rodriguez's plan to make her a more aggressive player at the net and improve her serve.
Simona Halep: The 22-year-old Romanian had a breakthrough season that launched her to a career-high No. 11 after beginning the year at No. 47. She won more main-draw matches (53, third on tour) than she had coming into this season (46), and her six WTA titles (the first six of her career) were the most on tour behind Williams. The only black mark on her season was her disappointing showings at the majors.
Sloane Stephens made the fourth round or better at all four Grand Slam tournaments. (Emmanuel Dunand/AFP/Getty Images)
Victoria Azarenka: She weathered the storm of controversy that surrounded her semifinal win over Stephens to defend her Australian Open title. But the best thing to come out of her 2013 season was her ability to play Williams tough, handing the No. 1 two of her four losses. Despite those highs, injury after injury marred her season, from a freak pedicure accident in Australia to a knee injury at Wimbledon. Azarenka played just 14 tournaments.
Sloane Stephens: Stephens was the last American standing at two of the four majors; she upset Williams at the Australian Open to make her first Slam semifinal and survived the carnage at Wimbledon to advance to the quarterfinals, losing to the eventual champion each time. Along with fourth-round appearances at the French Open and U.S. Open, the 20-year-old was able to equal or surpass her best showing at each Slam this season. Sure, she didn't do much else (she still has yet to make a tour final), but Stephens delivered at the biggest tournaments of the year.
American women: Williams and Stephens get their own special recognition, but on the whole this was a great year for the American women. Bethanie Mattek-Sands had the biggest rankings jump of player who closed in the top 50, going from No. 173 to No. 48 thanks to an impressive clay season. She defeated Sara Errani and Lisicki to advance to the semifinals of the Porsche Tennis Grand Prix as a qualifier, and she toppled Li en route to the fourth round of the French Open.
Jamie Hampton also got to the fourth round at Roland Garros, her best result at a Slam, thanks to a third-round upset of Petra Kvitova. Hampton carried that momentum into the grass season, where, as a qualifier at the Aegon International, she upended top-seeded Agnieszka Radwanska and Caroline Wozniacki on her way to her first WTA final.
And then there was 18-year-old Madison Keys, who impressed in her first full year on the WTA Tour. She jumped 111 spots, to No. 38, with a 34-21 season that included four quarterfinals. Tack on Alison Riske's improvement, Victoria Duval's star-making upset of Sam Stosur at the U.S. Open and strong junior performances from Taylor Townsend and Tornado Black, and there was lots to be happy about for the U.S. women.
Eugenie Bouchard: If you offered a bet at the start of 2013 that Bouchard would be the highest-ranked teenager at the end of the season, you probably wouldn't have had many takers. Overshadowed by other young talents such as Stephens, Laura Robson and Keys, the 19-year-old Canadian got better as the season progressed. In her first full season on the WTA Tour, Bouchard defeated Ana Ivanovic at Wimbledon and Stephens and Jelena Jankovic at the Tokyo Open; climbed 122 spots, to No. 32; and earned the Newcomer of the Year award.
Kimiko Date-Krumm: For just the second time since her comeback began in 2008, the 43-year-old ended the season inside the top 70 (No. 65). She made the third round of the Australian Open for the first time since 1995 and the third round of Wimbledon for the first time since reaching the semifinals in 1996. Incredible effort.
Jelena Jankovic finished in the top 10 for the first time since 2010. (Dean Mouhtaropoulos/Getty Images)
Agnieszka Radwanska: She never really recovered after losing to Sabine Lisicki in the Wimbledon semifinals. The weight of that lost opportunity to win her first Slam (she would have faced Bartoli, who hadn't beaten her in seven meetings, in the final) seemed to keep her down during the second half of the season. It was important for Radwanska to back up her strong 2012 season, and for the most part she did, closing at No. 5 with three titles and 56 victories (second to Williams' 78). She's a solid top-five player despite a lack of power, and her creative shot-making skills still make her one of the most entertaining players to watch.
Jelena Jankovic: The Smiling Serb finished in the top 10 for the first time since 2010, which is right around where she should be. After two and a half years of underperforming, the 28-year-old Jankovic finally started putting in the work on the practice courts and getting back to the type of counterpunching that worked so well for her five years ago, when she became No. 1.
Sabine Lisicki: It was a tremendous effort to make her first Slam final, beating Williams and Radwanska in nail-biting three-setters at Wimbledon. But facing Bartoli for the title, Lisicki's nerves failed her and her tears during the match were tough to watch. The 24-year-old German's ability to play her best at the All England Club is nothing new; her entire career has revolved around it. So it continues to be unfortunate and somewhat puzzling that she can't translate that success elsewhere. She failed to get past the third round of the other three majors and went 0-3 in tournament finals.
Sara Errani: The 26-year-old Italian's season wasn't as successful as 2012, but she still finished seventh and played her best tennis on clay, winning the Mexico Open and making consecutive semifinals at the Madrid Open, Italian Open and French Open. By the time the U.S. Open rolled around, she admitted that the pressure of following up her big 2012 season was getting to be too much for her. Still, Errani proved that she has staying power this season.
Laura Robson: Wimbledon covers all wounds when you're British, and Robson's run to the fourth round of her home tournament salvaged a lackluster year. She continued to channel her best against the big names, with victories over Petra Kvitova at the Australian Open, Radwanska at the Madrid Open and Venus Williams at the Italian Open. The inconsistency and inability to close out sets and matches are still a big issue. During one spring stretch, she had four straight three-set losses that ended in a 6-1 set, and in three of those matches she won the first set. Still, she finished ranked higher than she was last year, at No. 44, and the fact that at 19 she was able to handle the pressure to become the first British woman to make the second week of Wimbledon in 15 years makes it a pretty good year.
Maria Sharapova's season ended early because of a shoulder injury. (Julian Finney/Getty Images)
Maria Sharapova: It was a solid season for Sharapova, but a player of her caliber expects more than two titles in 10 tournaments. She played only one match after Wimbledon, an ugly loss to Stephens at the Western & Southern Open (the two combined for 113 unforced errors), and then shut down her season because of a worrisome shoulder injury. Even setting aside her injury woes, two bad losses at the Slams and her continued inability to beat Williams detracted from Sharapova's season. Sharapova looked dominant at the Australian Open, dropping just nine games heading into the semifinals, but she lost easily to Li 6-2, 6-2. She was part of the Wacky Wednesday carnage at Wimbledon as well, losing to No. 131 Michelle Larcher de Brito 6-3, 6-4. And then there's Serena. Four of Sharapova's seven losses this season were to Williams, including the finals of the French Open, Sony Open and Madrid Open. That's 13 losses in a row in the series.
Petra Kvitova: The sixth-ranked Kvitova, 23, actually finished the season two spots higher than last year, but 2013 still seemed like a disappointment, primarily because of her performance at the Slams. She lost in the second round of the Australian Open and third round of the French Open and U.S. Open. When she became a favorite to win Wimbledon for the second time after Williams crashed out in the fourth round, Kvitova lost to No. 20 Kirsten Flipkens 4-6, 6-3, 6-4 in the quarterfinals.
Caroline Wozniacki: Wozniacki finished the season where she started, at No. 10. Though she won the Luxembourg Open in her final event of the season, her best result was a run to the final of the more star-laden BNP Paribas Open, where she lost to Sharapova. She failed to make it past the fourth round of a Slam, with losses to Svetlana Kuznetsova, Bojana Jovanovski, Petra Cetkovska and Camila Giorgi. Over the last two seasons she is 4-13 against top-10 players, a far cry from the numbers she put up during her time at No. 1.
Maria Kirilenko: In June, the 26-year-old Russian cracked the top 10 for the first time after a fantastic start to the season, which included a career-best run to the quarterfinals at the French Open and the semifinals at the BNP Paribas Open. Then she disappeared. She lost in the first round of Wimbledon and went 7-7 the rest of the way, falling to Halep 6-1, 6-0 in the third round of the U.S. Open. She finished at No. 19, a disappointing end to what began as a promising year.
Sam Stosur: A late-season surge of one title and two runner-ups salvaged a rough season for Stosur, who lost in the third round or earlier at all four Slams and didn't make a semifinal until winning the Southern California Open in early August. She has slipped to No. 18, her first year-end ranking outside the top 15 since 2008.
Truant (at least for the majority of the year)
Mona Barthel: When she's good, she's very good. But when she's bad, things unravel. In her first four tournaments, the 23-year-old German made the final of the Hobart International and the Open GDF Suez and the semifinals of the ASB Classic. Her season fell apart from there. From the Sony Open in March until the end of the season, Barthel won back-to-back matches at just one tournament.
Nadia Petrova: The 31-year-old Russian, who struggled with injuries in the second half of the year, went from No. 12 to No. 105 after a 9-13 season that included first-round losses at all four Slams.
Marion Bartoli: She stunningly retired less than two months after winning Wimbledon, with her body and mind unable to withstand the tour grind anymore. Bartoli milked every last drop of her talent to put together a fine career.
Anna Chakvetadze: The former No. 4 didn't play a match all year and formally announced her retirement at age 26 in September. A talented ball-striker who reached the U.S. Open semifinals in 2007, injuries and being victimized by a home invasion derailed her career.
Jill Craybas: The 39-year-old American called it quits on a 17-year career highlighted by a win over Williams at Wimbledon in 2005 and five doubles titles.
Elena Baltacha and Anne Keothavong: