Martin Gould recorded his best win of the season when beating Ronnie O'Sullivan 4-1 to progress to the last 16 of the English Open.
O'Sullivan had been one of the tournament favourites following two early wins in Brentwood, but he was put in his place by Gould who turned in a polished display.
The opening frame of the contest proved key in deciding the outcome of the match, O'Sullivan in first with a run of 56 before missing frame ball and allowing Gould to pull off a crucial steal.
Gould kept his cool to pot a tricky final red along the side cushion and mopped up the colours, and then doubled his lead moments later thanks to a break of 60 in frame two.
O'Sullivan hit back with a typically brisk 78, but Gould didn't relent and finished the job in some style.
A break of 57 put him on the cusp of a famous victory, and he rounded off a good afternoon's work with a match-sealing hand of 61.
“It’s very early in the tournament but to beat Ronnie is a great scalp,” said Gould.
“I have to build on that, not go out signing and dancing, I have to stay in tournament mode and be ready for the game tonight.
“Snooker is a weird game, you can be flying off your nut for six months, and then you turn up for one event and you forget which end of the cue to use. Beating Ronnie means nothing if I go out and play like a balloon tonight.”
Gould though went on to lose 4-1 to Ashley Hugill in the evening session.