Olympic champion Elena Dementieva has crashed out of the US Open to new American hero Melanie Oudin. Fourth seed Dementieva suffered a stunning defeat as she was up-ended 5-7 6-4 6-3 by the teenager Oudin in the second round. The Russian, one of the favourites for the title, was out-hit and out-played by the 17-year-old world number 70, who handed Dementieva her joint earliest-ever exit at Flushing Meadows. Also out is fifth-seeded Jelena Jankovic, last year's runner-up, who was beaten 6-3 6-7 7-6 by Yaroslava Shvedova of Kazakhstan. Volatile top seed Dinara Safina flirted with an early exit for a second successive match, but held on to defeat Germany's Kristina Barrois 6-7 6-2 6-3 and reach the third round. World number one Safina had 15 double faults and 38 unforced errors during a two-hour, 13-minute match in Louis Armstrong Stadium, but the Russian was helped by her unseeded opponent's 43 unforced errors. Next up for Oudin will be 2006 champion Maria Sharapova who beat another American 17-year-old, Christina McHale, 6-2 6-1. On the men's side, Wimbledon runner-up Andy Roddick completed the night session with a clinical 6-1 6-4 6-4 win against Frenchman Marc Gicquel. Earlier in the day, Novak Djokovic kept the Serbian flag flying following the early exits of Jankovic and Ana Ivanovic. The fourth seed beat Australian Carsten Ball 6-3 6-4 6-4.