Mark Allen trails Barry Hawkins 5-3 after the first session of their World Championship second round match at the Crucible Theatre in Sheffield.
Hawkins twice led by a frame but Allen levelled on both occasions to leave the score 2-2 at the mid-session interval.
In frame five, Allen fired in a break of 64 but Hawkins replied with a 69 break to win and nudge ahead again.
Allen won the next to level again but a break of 71 helped Hawkins to a 4-3 lead and he then made it 5-3.
The players will resume their match on Saturday morning, with the final session on Saturday evening.
Allen progressed to round two courtesy of a thrilling 10-9 win over Welshman Matthew Stevens in the first round.
The Antrim player recovered from 9-6 down to win the last four frames and take victory.