American tennis is in what you could describe as a transition. With Andy Roddick retired and the Williams sisters not getting any younger, there are empty places atop the American tennis ladder.
Over the next few years, there will be a number of young Americans who slide under the radar as they move on from the junior level. They will be grinding away on the Futures circuit and Challenger Tour vying for valuable ranking points to unlock main-draw entries.
But once they have gained experience and resurfaced onto the Grand Slam scene, who can you put your money on to lead another era of American tennis dominance?
Here is a brief insight into five young guns that just might be the future.
Jack Sock first started gaining attention after a strong 2010, when he won the USTA Boys 18s Nationals and U.S. Open Junior title. But it was not until the following year that the Nebraska native seriously put his name on the map.
Sock was granted a main-draw wild card for the U.S. Open in 2011, and he put it to good use.
In the first round he sealed his first ATP match victory, defeating Marc Gicquel in four sets. As a reward he got to face off against his childhood idol, Andy Roddick, who eventually dispatched Sock 6-3 6-3 6-4.
His singles success was a short-lived memory, as his ride at the Open was only just beginning. One week later, he lifted the mixed-doubles trophy after upsetting the field with fellow American Melanie Oudin.
With Roddick’s power, Federer’s touch and Nadal’s heavy ball, Sock has a unique playing style. Like his idol Roddick, he has a big forehand paired with an even bigger serve. He certainly does not shy away from the net, and he likes to mix in the serve-and-volley on occasion.
Sock's future looks bright. His game can mix it up with the best of them, and more importantly, he has demonstrated that he can handle the big stage—there is none bigger than Flushing Meadows.
Denis Kudla was born in the Ukraine but landed in Fairfax, Va. when he was one year old and has called America home ever since. Despite the temptation of a college career under the sun at USC, he chose the tougher option of the pro circuit.
However, he quickly showed he deserved to be out there on the tour when he made the quarterfinals of the 2011 Campbell’s Hall of Fame Championships. His career-best performance to date was made even sweeter by overcoming the big-serving Ivo Karlovic and Grigor Dimitrov to get there.
In his young career, he has already developed a rivalry with Sock that could flourish in the years to come. In the 2010 Junior Boys U.S. Open final, Sock beat Kudla to take the title. But Kudla avenged the loss at 2012 SAP Open, where he beat Sock in three tight sets.
Kudla's backwards cap is not his only resemblance to the veteran Lleyton Hewitt. He also boasts a killer two-handed backhand. Like a teenage Hewitt, Kudla proved higher opponents do not intimidate him, which places him in good position to rise in the rankings and chase the top 100.
Townsend made headlines at this year's U.S. Open for how she was treated by the USTA regarding her weight and fitness. However, she has shown that it is her tennis game that deserves all of the attention.
The left-hander from Atlanta has had a strong 2012. She had a perfect start to the year Down Under, running away with the Junior Australian Open Singles title. It continued at the U.S. Open Juniors where, amid the controversy, she still managed to reach the quarterfinals.
Her slightly larger build should not be a concern for her future success. Marion Bartoli and Serena Williams have illustrated that you don’t need to be chiseled to go deep in a Grand Slam. Like the latter, her game is built on power and being comfortable camping on the baseline.
Townsend is the youngest of these five emerging American talents, and a true talent is what she is.
You can look at her dispute with the USTA in a number of ways. But the fact that they care and are concerned about her long-term health and fitness reinforces the potential they see in her.
Samantha Crawford stands at a towering 6'2", placing her in the same ranks as superstar Maria Sharapova in a back-to-back competition.
Crawford certainly does not measure up to Maria’s triumphs on the court, but as a teenager she has already found success at the U.S. Open in both the juniors and main-draw events.
Before she won the Junior Girls title in 2012, she had already clocked in a lot of hours on court at Flushing Meadows. Crawford made it through the qualifiers and ended up with a debut in the main draw of the U.S. Open against the young Brit Laura Robson. Crawford put up a good fight, earning set point in the second set, but was not able to convert and move past the first round.
At just 17 years old, she has already exhibited a game that can compete beyond the junior level. She exploits her tall frame and leads with her big serve. She is not a player who is going to get hooked into a long rally and instead goes for her shots early.
In the future, if Crawford is able to emulate Sharapova’s style, she will be in a good position to rise in the rankings. You can already lock her serve in as a weapon, and as she develops, her experience will put her in better positions to counterpunch or finish the points early.
He might be the long shot of this group, but that is what makes his development that much more interesting.
After receiving a wild card into the U.S. Open this fall, Johnson quietly became a fan favorite. The home-crowd support carried him as far as the third round. He eventually fell to Richard Gasquet, but not before beating Ernests Gulbis.
Johnson completed one of the greatest college careers in NCAA tennis history. In his last Division I season, he went undefeated and won his second NCAA Singles title in a row. He was also part of the Trojans team that captured the overall title in all four of his years at USC.
Fellow American John Isner paved the way for college standouts to be successful in a game that increasingly demands you to start on the circuit from a young age. Johnson bodes a creative style of play that was clearly nurtured in the college system.
He adds a lot of variety into his game that takes elements of Fabrice Santoro and Bernard Tomic's signature touches. He is a strong defender, and opponents have to do a lot just to get the ball past him.
Johnson is three classes short of getting his degree from USC. But it looks like he is in no hurry to finish, especially if his college dominance is transparent on the professional level.