Lines, 46, took a 9-0 first-session lead in their Betfred World Championship best-of-19 frames first round qualifier at Ponds Forge in Sheffield on Wednesday. The match concludes on Thursday.
Hong Kong’s On Yee could have been forgiven for being jaded, coming 24 hours after losing her World Ladies Championship title in Leeds.
On Yee, 25, lost 6-4 on Tuesday to Reanne Evans, who regained the world title she lost 12 months ago. The 30-year-old Dudley potter’s victory means she is now an 11-time world champion.
Evans was beaten in the 2015 semi-finals by On Yee, who had the highest break of this year’s final with 72 to lead 3-1 early on. Evans battled back and from 4-3 adrift took three frames in a row to secure the silverware and prize-money of £1,200.
Fellow Leeds potters Sanderson Lam and David Grace – who are based with Lines at the Northern Snooker Centre – had mixed fortunes.
Lam, 22, trails Kurt Maflin 6-3, while Grace – the 30-year-old who shot to prominence reacing the semi-finals at the UK Championship in York – leads Brendan O’Donaghue 5-1.
Sheffield’s Joel Walker, 22, is bidding to be the first player from the Steel City to play at the city’s famous Crucible venue. After the opening session, he leads Scott Donaldson 5-4.
“It would mean everything to qualify for the worlds,” said Walker.
“It would be a step forward in my career and take some of the pressure I put on myself off. The reason I took up the game was to play at the Crucible and become world champion.
“No one from Sheffield has ever played there so it would be great to experience playing at the Crucible.”
Keighley’s Chris Melling plays David Morris on Thursday.
Tickets for the qualifiers cost £10 per day or £20 for any three day.
To book call the box office on 0114 2233777 or visit www.worldsnooker.com/tickets