Beating Ricky Walden 5-2 in the second round of snooker China Open here Thursday, Mark Selby ensured his world top ranking as the list is to be released next week.

World No. 42 Jack Lisowski continued his top form following first-round win over Judd Trump as the 21-year-old came from behind to beat Mark Davis 5-4 in the second round.

As currently world top player Trump was stunned by his good friend Lisowski, Selby's second-round victory guaranteed that "Mark the Shark" will take the lead on world ranking.

The 30-year-old Englishman shot a 3-1 lead with a break of 91 in the first frame before interval. Walden fought back one frame but couldn't find his pace anymore.

"Obviously I'm happy (to go back to No. 1), but the main thing is to still be in and win this tournament and then lead it to the World Championships," said Selby, who meets Mark Williams next on Friday after Williams captured the victory against Allister Carter at 5-4.

Fluent cueman Lisowski came from behind two times to level the score at 2-2. Though the next two scrappy frames went to Davis, Lisowski carved out the victory with runs of 80, 71 and 81 in the last three frames.

World No. 3 Neil Roberston met little resistance as the Australian took a 5-1 easy victory over world No. 7 Mark Allen.

Last year's runner-up Stephen Maguire also looked sharp by defeating Barry Hawkins 5-1. Endi