BIRMINGHAM, England - Lin Dan and Xie Xingfang, the two top-seeded titleholders and one of China's most famous sporting couples, reached the quarter-finals of the All-England Open on Thursday.

China's Lin Dan returns a shot to Indonesia's Simon Santoso during the men's singles second round at the All England badminton championships in Birmingham, England March 8, 2007. [Reuters]

The two celebrated by going on Birmingham's big wheel together after winning the men's and women's singles titles within a couple of hours of each other last year, and their straight games victories Thursday created visions of another combination of success and romance in Sunday's finals.

Lin looked determined to reassert himself as the world's best player as he advanced with impressive changes of gear during a 21-14, 21-18 win over Simon Santoso, a nimble Indonesian qualifier, while Xie overcame Salakjit, a Thai qualifier, 21-11, 21-10, appearing not to use a couple of gears at all.

Xie seemed pleased to do enough to control the rallies and to dominate her opponent, while saving her energies for possible tougher struggles to come.

"I deal with the pressure of the situation on court better than anyone else," she said.

"I choose the right shot without taking too many chances and not all of my opponents do that."

Lin appeared keen both to defend the world's oldest title and to return to the winner's podium after his unexpected failure in the last Super Series tournament in Kuala Lumpur.

There the surprising left-hander was beaten in the second round; here he advanced to the quarter-finals with a performance which displayed what a uniquely versatile competitor he is.

Lin would play at different paces, accelerating when he felt he needed a run of points, and would hit at different speeds, which was demoralizing for the admirable Santoso, even though he stuck to his task as best he could.

"The match was fine - it wasn't too hard," Lin said.

"I was very much looking forward to playing Taufik and Gade, but they are out," added Lin, referring to the withdrawal of Olympic champion Taufik Hidayat and the first round defeat of former world number one Peter Gade.

"I was surprised - I was expecting him to win," Lin said of Gade's loss to Dicky Palyama of The Netherlands.

"It's very disappointing that neither of them is here now."

Lin's next opponent is not, as the seedings suggested, Muhammad Hafiz Hashim, because the former All-England champion from Malaysia was steadily outplayed by Sony Dwi Kuncoro, who looked superbly prepared for the third tournament of the series.

Kuncoro won 21-11, 21-14, and was mobile, strong, and excellent in defence, causing Hafiz to give up most of his more ambitious airborne attacks in the second game and try a few more rallies in the forecourt. But the number eight seed had little more success there.

Xie next plays her compatriot Jiang Yanjiao, the rising world number ten who brought down the fifth seeded Yao Jie in the first round and followed it with a 21-12, 21-12 win over Malaysia's Wong Pei Xian.