World number one Judd Trump was forced to fight back from 3-1 down for the second match in a row to keep his English Open hopes alive.
The 31-year-old from Bristol squeezed past Yuan Sijun 4-3 in the second round, just a day after avoiding a shock exit to Louis Heathcote by doing similar.
Trump reeled off breaks of 73, 83 and 67 to claim the final three frames as Yuan failed to pick up a single point.
“Today was a little bit better from 3-1 down. I am happy with the way I ended the game but there were still a lot of missed balls and careless shots,” he told the World Snooker Tour.
“He didn’t really do a lot wrong from 3-1, I made three good breaks.
“Hopefully I can keep digging myself out of trouble and play a little bit better next game.
“The form is there, it’s not showed itself in this event, but I’m still battling away. Tomorrow is the big day.”
Six-time world champion Ronnie O’Sullivan beat Ryan Day 4-1 to set up a third-round tie against Matthew Stevens.
“I thought I missed a few balls. I played all right I suppose. I probably played better than I felt,” said O’Sullivan afterwards.
“It’s weird with no crowds, certain players need an atmosphere to get up for it. When you play a good shot you excite yourself and you don’t need the crowd to get you going.
“But when you are struggling you need a crowd to force you to find something. We’ve got to get used to it.”
Robertson cruises through
Neil Robertson cruised into the third round of the English Open with a comfortable 4-2 defeat of Mark Joyce in Milton Keynes.
The Australian didn't drop a frame in his opening match and he quickly took command of this second-round encounter, breaks of 102 and 56 helping him establish a 3-1 lead.
Joyce did close the gap to one thanks to runs of 72, 54 in frame five but Robertson closed out the match in typically ruthless style as he bids to improve on a fairly modest record in the Home Nations Series curtain raiser.
Elsewhere, World Championship runner-up Kyren Wilson didn't need too many fireworks to breeze past Gao Yang, nor did Alexander Ursenbacher as he beat Nigel Bond 4-0.
Tom Ford, Jimmy Robertson and Matthew Stevens were other notable names to make it through to the last 32.
Allen stunned in Williams whitewash
Mark Allen suffered a shock exit at the hands of Robbie Williams as the Northern Irishman slipped to a 4-0 defeat.
Allen came into the match having won the two previous meetings between the pair but he was never at the races on this occasion as Williams dominated throughout.
Breaks of 80 and 70 saw Williams race into a 2-0 lead and when he added a run of 61 in frame three, the writing was already on the wall for Allen who was unable to recapture the heavy scoring he has produced of late.
Allen did have his chances to respond in frame four but Williams pounced on more unforced errors from his opponent as he wrapped up one of the biggest wins of his career.
There was another big shock as Steven Hallworth edged out Yan Bingtao 4-3 while Liang Wenbo trounced Martin O'Donnell 4-1.