By A.S.

THE PEDIGREE: The 22-year-old Jankovic is the daughter of two economists (can’t you tell?) from Belgrade, Serbia. But it was at the Bollettieri Academy in Bradenton, Fla., where she’s been training since she was 12, that she became a sure-shot prodigy alongside Maria Sharapova. After disappointing early results, Jankovic made her breakthrough in 2006, beating Venus and Serena Williams and reaching the semifi nals of the U.S. Open.

THE PERSONA: Jankovic laughs loudly and quickly and can talk about Serbian music and her university studies with equal aplomb. She’s spunkiness personified, the tour’s resident tough girl. Which makes sense, because she grew up in the middle of the Serbian civil war and started her tennis career only after it became too dangerous for her to travel crosstown for piano lessons.

THE GAME: When Jankovic hits a ball, she does it without fear, without regard for the last shot, the last game, the last set, or the last match. That clarity of purpose, and a lethal two-handed backhand, is how Jankovic pushed Justine Henin-Hardenne around like a sparring partner for the better part of two sets in last year’s U.S. Open semifi nals. But she can lose that clarity in a hurry: After a mild disagreement with the chair umpire, Jankovic blew her lead over Henin-Hardenne as quickly as she had amassed it. “I had the match . . . I was dominating,” she said with a shrug afterward. “Then I lost my concentration.”

THE PROGNOSIS: There’s little doubt that Jankovic has game. One reasonable scenario is that she becomes the Jana Novotna of her day, winning the award for the Player Most Likely to Implode. But the other is that she tones down her gambler’s instinct just a bit and becomes a fixture in the second week of Slams.