The gloom surrounding the future of women's tennis in the United States lifted ever so slightly on Thursday as Beatrice Capra left her calling card. The daughter of an Italian immigrant and a tennis-playing American mother, the 18-year-old from Baltimore caused the upset of the day at the US Open by defeating French 18th seed Aravane Rezai 7-5, 2-6, 6-3. It was welcome relief for home fans following a run of depressing first-round defeats for American youngsters who are struggling to keep up with the factory belt of talented players coming out of eastern Europe. Capra was playing in her first WTA tour-level main draw, was the youngest player left and had the lowest world ranking at 371. Few, including herself, thought she would get this far. But having won a playoff competition for a wildcard into the tournament, Capra said that her self belief had grown. 'I think really it's the confidence that I had, you know, earning my way into this instead of them just giving me a wildcard,' she said of how she had coped with playing against a top-20 player for the first time. 'Every time I've just been given a wildcard I never do well. I like earning everything. I just think playing against tougher players in the wildcard playoff helped me a lot.' Capra's win earned her a huge ovation from a packed Grandstand Stadium as she was instantly earmarked as being a possible US saviour of the game here once the Williams sisters leave the scene. World number one Serena is not playing this year due to a foot injury and sister Venus is seeded third but at 29- and 30-year-old respectively, their years at the top are numbered. No other US player was among the 32 seeds and to date no one has stepped forward to grasp the baton. It's not that the facilities do not exist and players like Capra benefit from expert advice from such legends as Chris Evert, Billie-Jean King and Martina Navratilova. But so far it has all been to no avail. Capra, despite her win over Rezai, admits that she still has a long way to go before she can realistically be seen as a worthy successor to the likes of the Williams sisters, Lindsay Davenport and another Italian-American player, Jennifer Capriati. 'My defense was really good today, but I think for sure I am trying to be more aggressive and working my way up towards the net and closing out points at the net,' she said. 'I think that will help me a lot, developing a better serve and return. 'But I'm just going to go out there and do my best and see what happens.' Next up for Capra is a dream third-round showdown against the player she idealized as a youngster, Maria Sharapova. And she will be leaning on close friend Melanie Oudin for some pointers on how to play the Russian former champion. Oudin was the relevation of last year's US Open, defating Sharapova at the same third-round stage on a run into the quarter-finals, with Capra watching every second of that match back home on television. 'It was really inspiring to me because I played her a year before, and then she was getting to the quarters of a Grand Slam. It was just unbelievable, and I was so happy for her,' she said. 'I think she's pushed all of the Americans to do better. I talk to Melanie a lot, and I will for sure ask anything about Maria Sharapova.' 