Shaun Murphy and Matthew Stevens were locked at 4-4 after the first session of their quarter-final clash at the 888.com World Championship in Sheffield.
Playing each other for the first time since the 2005 Crucible final which Murphy won 18-16, it was Welshman Stevens who started the better.
Breaks of 46, 118 and 64 saw the two-time finalist race into a welcome 3-0 lead.
But back came Murphy with a break of 82 to make it 3-1, before winning a scrappy fifth frame to trail 3-2.
Stevens sunk another century, a break of 108, to win the next frame and give himself a two-frame cushion.
However, this year’s Malta Cup champion Murphy was in determined mood and breaks of 33 and 89 saw him win the next frame.
Stevens got in the final frame of the opening session, but missed his chances and Murphy won the frame with a composed 33 break.
In the other quarter-final match on the opposite table, Scot Stephen Maguire has taken a 5-3 lead over Nottingham’s Anthony Hamilton.
The former UK and European Open champion won a scrappy opener before a break of 63 saw four-time ranking event quarter-finalist draw level.
Milton’s Maguire won the next with a cool 106 break, before Hamilton pocketed runs of 79 and 42 to go ahead for the first time in the match.
But from then it was Maguire’s turn to control proceedings, a break of 42 and a clearance of 25 enough to take the sixth frame, before a superb break of 89 made it 4-3.
It soon became 5-3 when Maguire won the final frame on points 61-15 for a two-frame lead.
Both matches resume tonight with a maximum of eight frames due to be played.