Murphy dashes Zhao's hopes of lifting Crucible curse

However, snooker's biggest prize has so far eluded him in 19 previous attempts with his win over Hawkins earning him a place in the last four for only the third time.

Having resumed at 8-8, Allen took the opening two frames of Wednesday morning's session only to be pegged back by the 2013 finalist, who knocked in breaks of 70 and 83 in response.

The players traded frames before Allen constructed his third century of a high-quality affair to move 12-11 ahead.

In a dramatic final frame, Allen took control with a break of 59 and sealed his passage to the single-table stage after the Englishman underhit an attempted snooker on the pink just seconds after fluking a red to give himself the chance to force a decider.

Allen said he felt "relief more than anything".

He added: "I thought the second session was one of the best I have ever been involved in. It was really high-quality snooker.

"My heart sank when he fluked that red - I'm over the moon to get over the line. If you could have seen inner Mark when he didn't reach the pink, he was doing somersaults and then I potted a good yellow.

"I have won everything else. Why can't I win this? I am thinking about it because I come here every year thinking I can win it for the first time."

Allen will now face either Wu Yize or Hossein Vafaei in a best-of-33 encounter that begins on Thursday at 19:00 BST.

On the other side of the arena, Neil Robertson retained the two-frame advantage he held overnight after the first session on Wednesday. He will take a 9-7 lead against John Higgins into the final session of their quarter-final at 19:00 BST.

After extending his lead to 6-3 by taking the day's first frame, the Australian was forced to watch on as four-time champion Higgins knocked in a barrage of big breaks with runs of 51, 86 and 126 to draw level.

Robertson, whose only Crucible success arrived in 2010, crafted breaks of 60 and 95 on his way to reeling off the next three frames before Higgins countered with an 80 to set up an intriguing finale.

'What a way to lose'

Should Allen win the world title, he will become the oldest first-time winner in the modern era, eclipsing Stuart Bingham, who became champion in 2015, aged 38 years and 343 days.

At 47, that would also have applied to the likeable Hawkins but instead it proved to be a disappointing conclusion to a wonderful match in which he contributed 10 half-century breaks and two centuries.

"The big difference was I lost a couple of frames where I had the balls at my mercy," Hawkins said.

"[It was] unforgiveable not reaching the pink. It was a horrible way to go. I was gutted.

"What a way to lose. Knowing you have played an absolute terrible shot. It was a sinking feeling after trying so hard in a long match like that."