Mark Allen came back from the brink to win his first-round match against Southend amateur Sydney Wilson at the Welsh Open.
The world No 11 trailed 3-0 and was 54 down in frame four before recovering to earn a 4-3 victory, sealed with a 112 break in the deciding frame.
Allen told World Snooker's official website: "I didn't really see those first three-and-a-half frames coming. I couldn't get anything going and could not concentrate.
"It was probably in the back of my mind that I was playing someone on the amateur scene so should win, and I completely let it get to me."
Wilson later wrote on Twitter, in response to criticism of his safety play: "Got a kick at 3-0 up and 50 up on a pink. Massive but after that I didn't play as well.
"Gutted. The kick on the pink at 3-0 is replaying over and over in my mind still."
John Higgins inflicted a 4-0 defeat on Maltese veteran Tony Drago but 2002 world champion Peter Ebdon was on the wrong end of the same scoreline against China's Li Hang.
Ebdon dropped the opening frame despite a 50 break and never recovered, Li making 59 in the second and pushing on from there.
In the evening session, there were 4-0 wins for Mark Selby, Martin Gould, Jack Lisowski and, most notably, Noppon Saengkham.
The Thai player blanked six-time world champion Steve Davis, sparked by a 102 break in the first frame.
World No 2 Selby strolled past Joe Swail, with an opening 70 the only break of note, while Gould made 100 and 63 to finish off Thanawat Thirapongpaiboon and Lisowski breezed through against Adam Duffy.
Ken Doherty was another 4-0 winner, against James Cahill, while Ricky Walden enjoyed a 4-1 success against York's Paul Davison rounded off by breaks of 88 and 73.
Dechawat Poomjaeng beat Liam Highfield by the same scoreline but Dominic Dale had to come from behind three times to beat Antony Parsons 4-3.
There were 4-2 wins for veterans James Wattana and Dave Harold against Rod Lawler and Zhang Anda respectively.
Tom Ford beat Gareth Green 4-0, Anthony Hamilton saw off Michael Leslie 4-2 and Matthew Selt was a 4-1 winner against Khaled Abumdas.