Joe Perry stunned defending champion Mark Williams with one of the highest breaks ever compiled in the 29-year history of the Crucible.

The Cambridgeshire player produced a sensational 145 clearance on his way to a 5-3 overnight advantage against the world number one.

There have only ever been five higher breaks and all have been 147 maximums.

Perry's break easily eclipsed Paul Hunter's 132 as early leader for a £17,600 prize.

Williams struggled in his opening round against Dominic Dale though not surprisingly after becoming a dad for the first time 24 hours earlier.

Williams was never in front but should have finished on level terms. Instead, Perry obtained a snooker, received an unexpected free ball and later a reprieve when Williams went in-off after potting the final brown.

Perry cleared from brown to black and will look to consolidate his advantage in Friday's second, eight frames session.