Si Jiahui’s extraordinary run at the Crucible looked set to continue as he established an 11-5 lead over Luca Brecel after the second session of their World Snooker Championship semi-final.

The 20-year-old reeled off his third century of the match plus five more breaks of 50-plus as he moved to within seven frames of victory when they resume their last four clash on Friday evening.

Si, ranked 80 in the world, is aiming to become the youngest Crucible finalist in history and also the first debutant to win the tournament since Terry Griffiths in 1979.

And his stunning pot success had the pundits purring with former world champion Dennis Taylor telling the BBC: “I’ve been coming to the Crucible since 1977 and I’ve enjoyed watching this young player as much as anyone I’ve ever seen here.”

Showing no sign of nerves, Si got off to a quickfire start with a break of 64 before fluking a snooker by easing the white into the jaws of the top right pocket.

After failing to extricate himself, Brecel showed his frustration by slamming the white off the table, incurring a warning from referee Rob Spencer, but responded with a 65 to reduce Si’s lead.

A remarkable long blue was the highlight of a 122 break from Si in the following frame, and further back-to-back breaks of 89 and 58 moved the Chinese player five frames clear at 9-4.

Brecel, who was not doing a lot wrong, won the 14th frame in two visits but the irrepressible Si maintained his astonishing long-pot success rate as breaks of 55 and 71 moved him within sight of a place in the final.