American qualifier Melanie Oudin, the world 124, sent Serbian sixth seed Jelena Jankovic crashing out of Wimbledon on Saturday with a 6-7 (8/10), 7-5, 6-2 triumph to make the last 16.

Oudin, just 17 and making her Wimbledon debut, next faces either Poland's Agnieszka Radwanska or China's Li Na for a place in the quarter-final.

The Serbian, who has never made it beyond the fourth round, was a break to the good at 4-3 in the opener before the battling Oudin levelled at 5-5.

Jankovic's greater experience told in a marathon tiebreak which she took 10/8, but the afternoon threatened to slip away from her when she required lengthy treatment on an injury to her left groin at the changeover.

Oudin, the youngest player left in the draw, was ahead at 1-0 in the second set, but was pegged back at 2-2 by the Serbian who was playing in her sixth Wimbledon.

But the American held her nerve to go to 3-2 and wrapped up the set in the 12th game to level the Court Three clash.

Jankovic was clearly wilting in the 30-degree heat and was broken in the third and seventh games before Oudin clinched victory on her second match point with a sweeping forehand.