Judd Trump cues up win in Bucharest as Ronnie O'Sullivan eases through

The former UK champion trailed 3-2 in Bucharest and looked to be heading for the exit door only for Woollaston - claiming three frames with runs of 55, 66 and 59 - to spurn his chance when the winning post beckoned.

Elsewhere, five-times world champion Ronnie O'Sullivan was a 4-1 winner against David Gilbert in the evening session in the Romanian capital.

O'Sullivan rolled in knocks of 87, 77 and 68 to move 3-0 clear after 33 minutes. Gilbert won his only frame of the night with a 74, but further crisp knocks of 50 and 41 secure O'Sullivan a meeting with Mark Allen in the last 16.

“Today I felt a bit more confident among the balls and made a few more breaks,” he said. “There are so many tournaments that you are bound to play well in some of them. David is one of the best cueists on the tour so it’s a good result for me tonight, and Mark Allen will be a great test in the next round.

“Last season I had a lot of stuff to sort out away from the table, I got myself into a bit of a twist. Hopefully, I can put that behind me now and play a proper schedule. As long as I put the work in, I’m sure there will be one of two tournaments where I catch fire and pick up some silverware.”

World number four Trump last reached the last eight of a tournament at the China Open in April, but will start a strong favourite to overcome Andrew Higginson in the last 16.

Trump contributed 105 and 64 before a closing 89 ended his fellow Englishman's prospects.

The turning point of the match came in the sixth frame when Trump laid a fine snooker after his opponent had missed a black off its spot.

Trump made him pay a heavy price before snatching the frame and then drilling a long red home to set up his winning run.

“My safety wasn’t great, but otherwise it was one of the best matches I have played this season,” said Trump.

“It was a good quality match and Ben will be disappointed to lose.

"There was a moment in the first frame when he declared a foul on himself when it looked like he was guaranteed to win the frame, that wouldn’t happen in most sports. He deserves a lot of credit for that."

In other matches, world champion Mark Selby completed a 4-2 success against Dominic Dale.

Selby always looked the likelier figure. He won the first with a 67 before Dale restored parity courtesy of a 72.

A 66 saw Selby move ahead before he finally clinched his progress by winning a sixth frame that lasted 49 minutes.

2005 world champion Shaun Murphy suffered a shock reverse going down to 4-1 to Mark Davis.

Northern Irishman Allen made 51, 53 and 122 in his 4-0 win over Daniel Womersley while Liang Wenbo was a 4-1 victor against Zak Surety.

Alfie Burden defeated Yu De Lu 4-1 and Scotland's Scott Donaldson recorded an impressive 4-3 victory over world number 32 Luca Brecel.

Zak Surety 1-4 Liang Wenbo

Ben Woollaston 3-4 Judd Trump

Alfie Burden 4-1 Yu De Lu

Mark Selby 4-2 Dominic Dale

Daniel Womersley 0-4 Mark Allen

Ronnie O'Sullivan 4-1 David Gilbert

Shaun Murphy 1-4 Mark Davis

Luca Brecel 3-4 Scott Donaldson