Gilbert, playing in his first World Championship semi-final, is 13-11 in front following the second day of the contest at the Crucible Theatre.

Higgins, a four-time world champion, was 10-6 behind but managed to cut the lead by winning five of the eight frames played tonight.

The Scot, who has made several uncharacteristic mistakes in the match so far, knocked in the highest break of the tournament with a 143 – just four shy of a maximum – in the 21st frame.

Gilbert brought the comeback to a halt with a 91 of his own to go 13-9 in front before Higgins won a scrappy penultimate frame.

Higgins also claimed the last frame of the night to set up an intriguing conclusion tomorrow.

In the other semi-final, Judd Trump, seeking a first world title, leads qualifier Gary Wilson 9-7.

Trump, favourite for the tournament, reeled off four consecutive frames to lead 9-6 before Wilson recorded a break of 77 to keep him in contention heading into tomorrow morning's third session.

Wilson had edged 6-5 in front thanks to a score of 65 but Trump found his form, stroking in breaks of 73, 123 and 75 to seize control.

Both semi-finals, which are first to 17 frames, will be played to a finish tomorrow.