One shot from losing in the first round of qualifying, Melanie Oudin will now be playing in the second week at her first Wimbledon. It has been a surprising, thrilling run for Oudin, a determined 17-year-old from Marietta, Ga., who still has many more friends and acquaintances in the junior ranks than in the main draw of the main event. But Oudin’s junior days are behind her now, as she proved beyond a reasonable doubt on Saturday by thinking and hustling her way to a 6-7 (8), 7-5, 6-2 victory over sixth-seeded Jelena Jankovic of Serbia, who was ranked No....