Italian underdog Andreas Seppi saved two match points in a stunning 4-6, 7-5, 7-5 win over world number four Lleyton Hewitt [Images] at the Sydney International on Thursday.

Hewitt, a four time winner of the Sydney International, looked in control after cruising through the first set and opening up a 5-3 lead in the second.

But Seppi, ranked 60th in the world, fought back to win the next four games and square the match, capitalising on unforced errors from Hewitt.

The Australian had two match points in the third set but Seppi fought him off on both occasions to register the biggest win of his career.

Seppi will play Igor Andreev in Friday's semi-finals after he beat fellow Russian Dmitry Tursonov 6-2, 3-6, 6-4. The other semi-final will be between second seed Nikolay Davydenko and American James Blake.

Blake beat Arnaud Clement 3-6, 6-1, 6-4 while Davydenko got a free-ride into the semi-finals after Paradorn Srichaphan [Images] pulled out with a thigh strain after beating Ivo Karlovic 7-6, 7-6 in a delayed second round match.

Paradorn was the eighth player in five days to pull out of the men's and women's tournaments through injury joining Kim Clijsters [Images], Daniela Hantuchova [Images], Nadia Petrova, Dinari Safina, Gisela Dulko, Carlos Moya [Images] and Thomas Johansson.

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