On a practice court in Flushing Meadows, N.Y., just after his first match as a professional, 17-year-old Jack Sock rallied with Roger Federer. Five years later, the two are on a collision course and could face off in the third round at Wimbledon, which starts today. Sock, 22, is in the midst of a breakout season. After missing the Australian Open recovering from pelvic surgery, he won his first title, the U.S. Men's Clay Court Championships in April at Houston, then in June reached the round of 16 at the French Open, becoming only the second American to take a set from Rafael Nadal in Paris. A matchup against an all-time tennis great might have frightened another player, but Sock has something other athletes his age don't — hardware. The Tampa resident won the 2011 U.S. Open mixed doubles with Melanie Oudin and took last year's men's doubles title at Wimbledon with Vasek Pospisil. Those experiences on a big stage, Sock said, helped against Nadal. "It's pretty special being across the net," said Sock, who lost 6-3, 6-1, 5-7, 6-2 to the nine-time French Open champion. "It's a little surreal at first." After the initial sheen wears off, however, things change. The competitor inside emerges, and he attacks his opponents with a combination of big serves and heavy forehands. Sock describes himself as an "all-courter" who uses his movement to force opponents to hit an extra ball. To reach Nadal at the French, Sock dispatched world No. 11, Grigor Dimitrov in the first round in straight sets, 23-year-old Pablo Carreño Busta in the second and 18-year-old Borna Coric, a former top-ranked junior, in the third. Troy Hahn, Sock's coach, believes his pupil's success in Paris was the result of months of hard work. "He had a great fall to end the year," Hahn said. "This year, he has just built on every tournament, starting at Indian Wells and into the French. Every week the guy is rock solid." Sock credits his rise up the rankings to the duo's focus on conditioning in training. "I think it's the sole reason I'm doing better," Sock said. "Ninety-five percent has been off the court." Hahn joined Sock's team at the 2014 BB&T Atlanta Open, where Sock bowed out in the semifinals against fellow American and friend John Isner, who has practiced with Sock at Saddlebrook in Wesley Chapel. Though Sock, who splits time between Tampa and Kansas City, Mo., where he grew up, has been hampered by injuries early in his career, Hahn praised his fitness and athleticism. "He's an unbelievable athlete, and he moves well," Hahn said. "His intangibles are amazing." Unlike many compatriots, Sock's favorite surface is clay — notoriously the hardest for American players to succeed on. Despite limited experience playing on claycourts growing up, he said he enjoyed competing on them. "He loves clay," Hahn said. "He's the one exception." While Sock has found success on the court, he has grappled with emotional strain on the sideline. In January, his brother Eric, 24, was diagnosed with Lemierre Syndrome and bilateral pneumonia. He recovered from the ailment but not before spending eight days on life support. Then, in June, Sock lost his grandfather after a lengthy battle with Alzheimer's. To honor his grandfather, Sock wrote, "4UGPA" on his shoes at the French Open. Sock's recent success catapulted him to a career-high ranking of 30. Now ranked 31, the 22-year-old is the fourth-youngest player in the top 32 and will be seeded at a Grand Slam for the first time in his career. Heading into what he calls his second "real" trip to the All England Lawn Tennis Club, Sock will look to defend his trophy in men's doubles. His partner, Pospisil, said Sock belongs to a select group of players who could have an impact on the future of the sport. "It's difficult to say what his peak can be, as that can depend on a lot of things." Pospisil said. "Of current American players, I think he's the one with the most potential." The third-seeded duo became partners at last year's tournament by chance. Pospisil, 25, was recovering from a back injury, and Sock needed a higher-ranked teammate to get into the draw. The pair went on to defeat three of the top five seeds, including the top-ranked Bryan brothers. Now, a year later, Sock and Pospisil are one of the premier doubles teams in the world, and their friendship has blossomed off the court. "Playing together turned out to be one of the best decisions we ever made," Pospisil said. "Not only because we won the tournament but because we also became great friends and developed a friendship that will outlive our tennis careers." The team plays Sam Groth and Sergiy Stakhovsky today in doubles, and Sock faces Groth in the first round of singles. Contact Shaker Samman at [email protected]tampabay.com or (813) 226-3394. Follow @shakersamman.