Cwmbran’s Jak Jones has secured his place in a second consecutive quarter final at snooker’s world championships with a 13-9 win over last year’s semi-finalist Si Jiahui.

Jones won four frames on the black yesterday as he moved 6-2 in front at the mid-session interval and extended that lead to 8-3 at one point only for Si to win the next three frames before the players won a frame each leaving the scores overnight at 9-7.

Both players were making mistakes and struggling for consistency with Si hitting his highest break of 84 in frame four.

The match went late into Friday evening, with extended frames and safety battles the norm as Jones attempted to contain the free-potting 21-year-old from China.

Indeed, the first frame on Saturday was in the same vein, lasting 55 minutes.

It was as you were when the players left the table for the mid-session interval on Saturday, with the players sharing a frame a-piece, this time with Si grabbing a frame on the black to close within one frame before Jones grabbed the 18^th with a clearance of 44.

At the mid-session interval on Saturday, neither player had made a half-century break and the match looked destined for extra-time with its slow-paced nature.

Jones took the 21^st frame with a 77, his highest break of the match to take him one short of victory before holding his nerve in another tense final frame with the Welshman potting the black whilst on the green but his opponent was unable to capitalise.

Finally, Jones took the win after just shy of nine hours playing time to reach the quarter finals.

In doing so, he became the first player since Matthew Stevens in 1998/99 to reach the quarter finals in his first two trips to the crucible, a stat made all the more surprising when you factor that these are Jones’ sole appearances in quarter finals during that period.

Next up for Jones will be world number two Judd Trump after he beat fellow Englishman Tom Ford 13-7.

Speaking after the match on BBC Jones said: “Last night was absolutely shocking, I didn’t feel good at all and I corrected it, went for a couple of hours practice which I wouldn’t normally do and felt much better today.”

“The couple of hours this morning allowed me to keep my emotions in check.

“I was lucky to be 6-2 up, I won four black ball frames in the first session. 9-7 after the way I played in the second session was probably really good, I just managed to fall over the line.

“With the season I’ve had last season and the season I’ve had this season it’s strange really, I don’t know what it is [about the world championships].

“Judd and Ronnie [O’Sullivan] are the two best players of this season or however many years, so they don’t get much tougher than that but I’ll try my best.”

O’Sullivan faces Wales’ Ryan Day in their round of 16 match which starts on Sunday morning.