Chinese Olympic champion Lin Dan swatted aside Dicky Palyama of Netherlands to reach the quarter-finals of the world championships on Thursday.
Fifth seed Lin, 25, seeking a record hat-trick of world titles, produced an array of spectacular diving returns and crosscourt winners in a 21-11, 21-11 victory to set up a last eight clash with third seed Peter Gade of Denmark.
The 32-year-old Gade, seeking his first title, was equally ruthless, brushing aside 10th seed Chan Yan Kit of Hong Kong 21-11, 21-12.
In the women's section, Hong Kong's world number one Zhou Mi, sporting a back brace, ended the good run of unseeded Japanese Ai Goto with a 21-11, 21-18 success.
Chinese second seed Wang Lin overcame Korean 12th seed Hwang Youn-hye 21-10, 21-13 but former champion Xie Xingfang, the fifth seeded Beijing Olympics silver medallist, was made to work hard by Thai Salakjit Ponsana before prevailing 21-16, 14-21, 21-9.
Austrian duo pull out
The Badminton World Federation (BWF) announced on Thursday that an Austrian male doubles pair had pulled out due to security concerns, after England withdrew its eight-member squad on the eve of the tournament on Sunday.
Peter Zauner and Juergen Koch allowed a walkover in the men's doubles to sixth seeds Mathias Boe and Carsten Mogensen of Denmark on Wednesday.
Their withdrawal follows England's decision to pull out its eight-member squad on Sunday, the day before the event began, citing a "specific terrorist threat".
"The two players left Hyderabad stating that they did not feel secure and that the upcoming Independence Day, together with the English team leaving, intensified their bad feeling," the Badminton World Federation (BWF) said in a statement.
An Austrian player and coach had remained at the tournament, the BWF said.
"The Austrian players state that they have taken advice from their embassy and the ministry of foreign affairs."
The BWF said, however, it was unaware of the Austrian embassy issuing any security alert after the first week of July.
India is on a high security alert ahead of the nation's Independence Day celebrations on Saturday.
Organisers have criticised England's decision to withdraw its team and dismissed media reports that powerhouse China had also contemplated pulling out on security grounds.