An array of top stars are in action at the Crucible on Saturday as the stakes are raised with Quarter-Final places up for grabs.
The stand-out tie of the day sees two titans of the baize face off in the afternoon as three-time champion Ronnie O'Sullivan faces twice champion Mark Williams.
The duo are regarded as two of the all-time great potters and look set to contest a three-day thriller at the home of snooker.
Despite his controversial remarks regarding the venue prior to the tournament, Williams is out for a good run this year and is determined to end his miserable record against The Rocket.
Williams has never beaten O'Sullivan at the Crucible, and has suffered three defeats to the 36-year-old in the past six years in Sheffield.
In 2006, O'Sullivan beat the Welshman in the Quarter-Finals, while in 2008 and 2010 the defeats for Williams came at this stage of the competition.
The Rocket made light work of a potentially tricky opener against China Open winner Peter Ebdon and still possesses an unrivalled natural talent that is capable of winning him any tournament should he match it with the correct temperament.
The morning session features two players looking to build on commanding leads as Ryan Day faces Cao Yupeng and Stephen Maguire looks to finish off Joe Perry.
Day stormed into a 6-2 lead after the first session on Friday and will be out to see off another Chinese ace having already defeated Ding Junhui.
Maguire looked in control during the first two sessions against the player known as 'the Gentleman', producing a number of skillful high breaks and all-round consistency.
He needs just two more frames to book his place in the Quarter-Finals and continue what has been a highly successful season for the Scot.
Seven-time world champion Stephen Hendry stunned defending champion John Higgins after winning seven of the eight frames in the second session on Friday evening.
The Crucible King looks to have followed up his 147 heroics and took advantage of a woeful showing from The Wizard of Wishaw to go within one frame of a famous victory which he will no doubt seal on Saturday.
Joint tournament favourite Judd Trump begins his last 16 tie with Ali Carter in the evening session as the youngster looks to continue his challenge for a maiden world title.
The youngster was struck down with food poisoning just hours before his match with Dominic Dale, but after a sluggish start, improved as the match went on and firing in a number of trademark long pots.
He is capable of moving through the gears and could cause former finalist Carter problems should he be given regular opportunities in among the balls.
The action gets underway at 10am GMT, with all matches being streamed live over the best of 25 frames over three seperate sessions from the Crucible Theatre, Sheffield.
Betfred.com World Championship 2012 Order of Play - Saturday, April 28:
Last 16
10am
18 Joe Perry 5-11 Stephen Maguire (final session)
23 Ryan Day 6-2 Cao Yupeng
2.30pm
17 John Higgins 4-12 Stephen Hendry (final session)
21 Mark Williams v Ronnie O'Sullivan
7pm
20 Ali Carter v Judd Trump
23 Ryan Day v Cao Yupeng (final session)
