Kyren Wilson remains in control of his World Championship second round match against Mark Allen as he takes an 11-5 lead into Monday’s final session.
Wilson, 24, outplayed Allen to lead 7-1 after the first session but the world number seven responded by taking the first four frames of the next.
The Northern Irishman knocked in two century breaks in the first two frames of Sunday evening’s play.
Kettering’s Wilson hit back to secure the final four frames of the session.
Wilson punished a series of poor Allen safety shots as breaks of 50, 55, 93 and 103 helped him win the first seven frames of the best of 25-contest at the Crucible Theatre.
Allen, who won his third ranking event, the Players Championship, last month, took the final frame of the morning session and looked transformed as he reeled off four in a row to mount a stirring comeback.
Wilson scored just one point in the first three frames of the night, with Allen compiling breaks of 122, 103 and 60.
A further break of 66 enabled the 2009 semi-finalist to reduce his deficit to two at the mid-session interval.
The Shanghai Masters champion fought back as a break of 82 made it 8-5, and Wilson went on to clinch the next three frames, the last on the black.
Allen must recover his best form on Monday if he is not to extend a run which has seen him fail to progress beyond the second round since 2011.
Sign up to My Sport to follow snooker news and reports on the BBC app.