Elena Dementieva has been eliminated from the U.S. Open after a stunning second round defeat to American teenager Melanie Oudin at Arthur Ashe Stadium.

The Russian fourth seed was sent off 5-7, 6-4, 6-3 by the 17-year-old world number 70 to become the first big-name casualty of the tournament.

Dementieva was the 2004 runner-up at the U.S. Open and Roland Garros and won the singles gold medal at the 2008 Beijing Olympics.

Oudin is the third-ranked American behind Serena and Venus Williams. She first drew major notice this summer at Wimbledon, where she upset former world No. 1 Jelena Jankovic en route to a fourth-round showing.

Now the Georgia native will face Maria Sharapova or Christina McHale, in the third round.

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