Ronnie O’Sullivan was in control against Pang Junxu as the seven-time winner finished the first session of their World Snooker Championship last-16 match with a 6-2 lead.
O’Sullivan claimed each of the first four frames, posting breaks of 58, 91, 50 and 63, before China’s No 27 Pang got off the mark by registering the contest’s first century break, making a 119.
The ‘Rocket’ swiftly hit back to secure frame six and after Pang took frame seven, O’Sullivan concluded the session by re-establishing a four-frame advantage to take into Sunday’s resumption.
Three-time champion Mark Williams advanced to the quarter-finals as he saw off Hossein Vafaei 13-10.
After going from 9-7 up at the start of the session to 11-8 ahead, Williams saw Vafaei take the next two frames to get within one of level pegging before the Welshman wrapped things up, finishing with a break of 115.
Williams’ last-eight opponent will be the winner of the marathon clash between John Higgins and Xiao Guodong, which could not be decided inside three sessions.
Facing a race against time to complete the match before the afternoon action commenced, four-time Crucible champion Higgins won two frames in a row after the mid-session interval but was frustrated by Xiao with the winning post in sight, as the Chinese star battled back to make it 12-11 just over four hours after the session began.
The pair were set to return to finish on Saturday evening, playing on the first available table following the scheduled matches.
There had been nothing to separate them after each of the first two sessions, which finished at 4-4 and 8-8 respectively.
And the third session followed the same pattern as no player led by more than one frame until after the interval on Saturday, with Higgins bouncing back from losing the opener by taking the next two before Xiao levelled things up at 10-10 by winning a mammoth frame that lasted more than an hour.
Scotland’s Higgins came out firing after the interval, making a break of 84 to take the 21st frame – his 2,000th at the Crucible.
With time running out in the session, Higgins managed to take the next frame despite missing a fairly straightforward pink at 65-0 up to open the door for Xiao, who was unable to amass the points he needed to overturn his deficit.
Requiring just one more frame to win the match at 1.40pm, the 49-year-old appeared on course for victory but let Xiao back in and was punished.
Zhao Xintong leads Chinese compatriot Lei Peifan 10-6 after winning the morning session 5-3.