Without fail, every year on the tennis circuit brings breakthrough performers. Andy Murray and Juan Martin Del Potro became men's regulars in the top 10, sparked by memorable summers, while teens Caroline Wozniacki, Agnieszka Radwanska, Alize Cornet, Victoria Azarenka and Dominika Cibulkova served notice among the women.
Are these some of the contenders in 2009?
Ernests Gulbis: Talent? This kid -- he's a baby-faced 20-year-old -- has it. How many can slam down ferocious serves and forehands as well as deliver those deft drop shots that drive opponents nuts?
Fernando Gonzalez springs to mind, yet the 2007 Australian Open finalist's serve frustratingly tends to vary, from all-out power to spin, too frequently.
Gulbis, Latvia's one-man show, threw scares into former training partner Novak Djokovic, Rafael Nadal and Andy Roddick at the French Open, Wimbledon and U.S. Open, respectively, before bowing out. Marat Safin, who eliminated Gulbis at the Australian Open, was no slouch, either.
Fine-tuning his go-for-broke style is inevitable, so the problem for Gulbis could be desire. He admitted last year he sometimes finds it difficult to motivate himself for lesser matches in less atmospheric surroundings; bad news considering the majority of tournaments fit that bill. Not much of a surprise, then, that his year-end ranking only rose a modest eight spots to 53rd.
Kei Nishikori: Observing Nishikori in the player lounge at the U.S. Open in September, you'd never know he held rock-star status in Japan and has lucrative sponsorship deals belying his low ranking. Uncluttered by the entourages that are the norm these days, Nishikori was nestled in the corner of a couch reading a book. (Yes, tennis players are literate.)
Unassuming on the court he's not. Nishikori, a roadrunner tipped for success by none other than Nadal and Roger Federer, excites with his leaping forehand, a rarity on tour, and outpourings of emotion. Fans who watched his five-set win over the determined David Ferrer at Flushing Meadows (albeit a slumping Ferrer) will attest to that.
Nishikori rose to prominence by winning a title as an 18-year-old qualifier on clay, his preferred surface, in Delray Beach, Fla. The achievement was all the more impressive considering he entered the event devoid of confidence. He became the youngest men's winner at the elite level since Lleyton Hewitt in 1998.
Praised for his racket speed, footwork and anticipation, Nishikori is destined to become Japan's highest-ranked men's singles player, surpassing Shuzo Matsuoka. Matsuoka ascended to 46th in 1992. The worry for the diminutive Nishikori, now 63rd, is akin to Hewitt's -- he lacks a major weapon.
Cilic slam-dunked more than a few of his tennis foes in 2008, aided by a big serve seemingly hereditary among Croats, a solid two-handed backhand and noteworthy returns. Described by his venerable coach, Bob Brett, as a thinker on court, the shy 20-year-old won his first title a week before the U.S. Open, then extended Djokovic to four tough sets in the third round in New York.
Outside the top 70 at the end of 2007, Cilic rests barely outside the top 20, a sizable jump.
Sam Querrey: Any American man -- apart from Roddick -- who gets to the quarterfinals of a Masters event on clay deserves special mention. Querrey did that in Monte Carlo in April. (Too bad he had to face Federer in the first round at the French Open.)
Like Gulbis, Querrey possesses a big serve and forehand. He used both to good effect against Nadal in the fourth round at the U.S. Open, then again when the pair met in the Davis Cup semifinals on terre battu in a rocking Madrid bullring. Continued progress would give captain Patrick McEnroe at least a little to ponder, surely, when it comes time to pick his squad for next year's tasty opening-round clash with Federer's Switzerland in the Davis Cup.
At 6-foot-6, Querrey's movement around the court, like Cilic, understandably isn't great. He's also working on his backhand.
Anastasia Pavlyuchenkova: The Russian charge continues.
Pavlyuchenkova is one of 11 in the top 50 and the youngest player overall, at 17½, in the top 100. Not quite following Maria Sharapova's tennis journey that began in remote Siberia and culminated in Florida, Pavlyuchenkova nevertheless left Russia to train at Patrick Mouratoglou's academy -- 2006 Australian Open finalist Marcos Baghdatis was groomed there -- just outside Paris.
Pavlyuchenkova became the youngest-ever qualifier at Wimbledon in June (though Jennifer Capriati and Martina Hingis, for instance, appeared at the All England Club at earlier ages) and made the most of it by topping two dangerous opponents, Cornet and Li Na, to reach the third round.
Using an attacking game from the baseline, Pavlyuchenkova won four minor-league titles, including two in a row to end the campaign. Her year-end ranking soared from 281st to 45th.
Sabine Lisicki: A big serve is a handy weapon for any pro, and Lisicki, another (yawn) disciple at Nick Bollettieri's academy in Florida, has it: She clocked the fourth-fastest delivery of 2008 with a 124 mph rocket in Cincinnati last summer. Thanks to modern technology, that amounted to the sixth-fastest of all time.
Similar in style to hard-hitting two-time Grand Slam champion Mary Pierce, according to Bollettieri, the 19-year-old German soared almost 200 places in the year-end rankings to 54th.
Lisicki qualified for the Australian Open, then knocked off Dinara Safina (before the Russian went on her roll) in the opening round. Soon after, Lisicki toppled Lindsay Davenport (before her knee troubles) on Fed Cup duty. She came close to winning a first title, too, falling short in Tashkent, Uzbekistan in October.
Lisicki blows hot and cold, and as Bollettieri acknowledges, the serve still needs work: She uncorked 13 double faults against, ironically, Elena Dementieva in the fourth round of the Sony Ericsson Open in the spring.
Sorana Cirstea: The last women's player of note from Romania might have been the surly Irina Spirlea, who bumped Venus Williams at the U.S. Open in 1997 and was tossed out of a match a year earlier for verbally abusing a linesperson.
Cirstea is more genteel, though like Spirlea, can thump the ball on both wings.
Cirstea took the good with the bad as she climbed from outside the top 100 to inside the top 40 in the year-end rankings. Not so pleasant were the double bagels she was handed at back-to-back tournaments during the clay-court season.
The 18-year-old, whom some say resembles Serb Ana Ivanovic, won her first title by overcoming Lisicki in Tashkent and ended the campaign by reaching the semis in Luxembourg.
While no threat in the Grand Slams in 2009, Oudin could be joining Mattek this year.
The 17-year-old models her game around retired seven-time Grand Slam champion Justine Henin -- never a bad thing -- though her forehand is a weapon, and she hits with two hands on the backhand. Like Henin, Oudin isn't one of the giants of the game, standing at 5-foot-4.
A native of Georgia with French roots, Oudin won her first professional title in July and reached her first top-tier quarterfinal, perhaps appropriately, in francophone Quebec City in October, dispatching U.S. Open quarterfinalist Sybille Bammer before losing to none other than Mattek. Oudin's year-end ranking progressed about 200 spots to 177th, making her the youngest American in the top 200.
Ravi Ubha is a frequent contributor to ESPN.com.