France's [Images] Paul-Henri Mathieu made up for last year's injury frustration here with a 6-3, 7-5 upset win over fifth seed Kenneth Carlsen to reach the quarter-finals of the ATP $400,000 Chennai Open on Thursday.

The 22-year-old Mathieu had to retire in the first round against the Danish left-hander in the 2003 event due to a wrist injury which sidelined him for seven months.

"This is where I got injured so it was satisfying today," Mathieu said.

The Frenchman, ranked 123rd in the world, next faces world number five and defending champion Carlos Moya [Images], whom he beat during the Davis Cup semi-final defeat against Spain last year.

Kristof Vliegen of Belgium saved two match points to topple sixth seed Yen-Hsun Lu of Taipei 1-6, 7-5, 7-6 in a two-hour-and-15-minute duel to oust all but the top two seeds in singles.

The 116th-ranked Vliegen, 22, cleverly mixed his game to escape twice from 2-5 down as the 21-year-old Lu, regarded as a rising talent from Asia, completely choked.

"In the end, it was a mental game," said Vliegen, looking forward to a good year after drawing top-notch first-round rivals and suffering an ankle injury in 2004.

The Belgian next plays second seed Paradorn Srichaphan [Images] of Thailand, the 2003 winner, who outclassed Nicolas Devilder of France 6-3, 6-2.

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