David Gray ground out a 5-3 lead over Lee Walker after a dour start to their second round match.

Gray, the 2003 Scottish Open champion, managed a highest break of only 30 during a below par display from the world number 12.

Welshman Walker, at 81st the lowest ranked player at the Crucible, recovered from 4-1 down to 4-3 with breaks of 79, 49 and 56 but Gray won the last of the night to carry a two-frame advantage into Sunday's second session.