Sheffield (England), Apr 28 (IANS): Welshman Ryan Day took a comfortable 6-2 lead over China's Cao Yupeng in the first session of their last-16 match at the world snooker championship here.

Debutant Cao had several clear chances but missed some crucial shots which allowed the Welshman to build up a commanding lead in the best-of-25-frames contest, reports Xinhua.

The 21-year-old rookie is the only Chinese player advancing to the last 16 after his compatriot Ding Junhui was upset by Ryan 9-10 in the first round.

With four frames advantage, the 32-year-old Welshman will go into the second session Saturday with confidence.

Australian Neil Robertson became the first to reach the quarter-finals after his 13-9 victory over David Gilbert Friday night.

The 2010 world champion looks good to win his second Crucible title after strong performance in the last two rounds. He will meet Ronnie O'Sullivan or Mark Williams in the last eight.

Stephen Maguire moved closer to the quarter-finals after he won six of the eight frames in the second session against Joe Perry, consolidating a 11-5 lead.

The world No.7 needs just two more frames Saturday to secure a last-eight berth against Stephen Hendry or John Higgins.

Seven-time "Crucible King" Hendry just stood on the brink of fending off the defending champion John Higgins as he led 12-4 after the second session.

Four times world champion Higgins now looks certain to fail in his bid to retain the title in front of the in-form 43-year-old veteran.

Hendry only needs one frame to book an 18th quarter-final appearance at Sheffield in the final session.

Second round (last-16, best of 25 frames) :

Neil Robertson (Australia) beat David Gilbert (England) 13-9; Stephen Maguire (Scotland) leads Joe Perry (England) 11-5; Stephen Hendry, (Scotland) leads John Higgins (Scotland) 12-4; Ryan Day (Wales) leads Cao Yupeng (China) 6-2.