Gilbert in driving seat despite missing maximum
David Gilbert came close to a maximum break as he marked his debut appearance in the World Championship semi-finals by establishing a 5-3 lead over four-time champion John Higgins.
Gilbert potted 15 reds and 14 blacks to raise hopes of clinching the £50,000 prize but the 16th seed ran out of position after sinking the final red with a cross-double.
It was a fine attempt by the 37-year-old, who is no stranger to a 147 having made the historic 147th maximum during a Championship League match in January.
And it proved a strong response from Gilbert after he had missed a golden opportunity to win the previous frame when he got the snooker he required only to miss the green off its spot.
Both players had struggled during a nervous opening session but it looked like Higgins, despite his exertions in dispatching Neil Robertson on Wednesday night, would be first to settle.
The Scot took the first two frames to establish an ominous-looking lead but Gilbert, who had won only one match in four previous Crucible appearances, responded well and drew level with a break of 94.
Higgins rode his luck to edge back in front in frame five despite attempting an inexplicable safety shot which led to Gilbert gaining the snooker he needed, only to throw away his chance.
Gilbert's maximum bid, which broke down on 113, pulled him level again at 3-3 and the underdog ended the session strongly, once again capitalising on a Higgins error to secure a 5-3 advantage.
The pair are due to resume their semi-final today.
Qualifier Gary Wilson, meanwhile, showed few signs of nerves as he shared the opening eight frames of the second semi-final with former finalist Judd Trump.
Wilson fired a break of 140 - just one behind the existing Championship best held by his opponent - as he nudged into a 2-1 lead in the match.
Trump won the first and last frames of a high-speed mini-session but mistakes played into Wilson's hands as there was little to choose between the pair.
Trump surged out after the mid-session interval with a brilliant 39 break to nudge himself back into a one-frame lead. But carelessness continued to cost him dear and an early mistake in the next allowed the seemingly nerveless Wilson to haul level again at 3-3.
The Newcastle player took advantage of a fluke to grab the initiative in a scrappy seventh, then was first in the balls to try to fashion an overnight lead.
After Wilson ran out of position on 25, Trump responded with a break of 54 which would ultimately prove enough to level the overnight score at 4-4.