Mark Selby underlined his Welsh Open title credentials with a 4-0 victory over Steve Davis to reach the last 32.
The reigning UK Championship and Masters champion top scored with a 144 break as he eased through in Newport.
Ding Junhui, who beat Selby in last year's final, defeated Thailand's Dechawat Poomjaeng 4-2, while Judd Trump won 4-0 against Mike Dunn.
John Higgins hit breaks of 120, 99 and 97 to beat Gareth Allen 4-1, while Mark Williams also beat Liu Chuang 4-1.
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Fellow Welshman Matthew Stevens progressed 4-2 at the expense of England's Alfie Burden and Ryan Day succumbed to a 4-1 defeat by Liang Wenbo of China.