Mark Selby will launch his Betfred World Championship title defence against an opponent who was accused of playing anti-snooker to reach the Crucible.
Ireland's Fergal O'Brien was part of a world record on Wednesday night when he won the longest frame in the history of professional snooker.
He needed two hours, three minutes and 41 seconds to win a decider against David Gilbert and book his place in the main draw.
The frame lasted 44 seconds longer than Kenyan athlete Dennis Kipruto's marathon world record, and Gilbert was upset by the ponderous tactics employed by O'Brien.
"The pace of play was diabolical from pretty much start to finish, and it wasn't me," Gilbert said.
Asked if it felt gruelling, Gilbert said: "It's worse than that - that's not snooker."
O'Brien responded to the criticism by saying: "In future would I like to play like that again? Absolutely not.
"Did I overplay shots, did I double-check stuff? Probably yes, but such was the pressure."
O'Brien had fancied landing a draw against Selby, who last year beat Ding Junhui in the final to add to his 2014 triumph, and their match will begin at 10am on Saturday as the tournament gets under way.
The 45-year-old Dubliner said of Selby: "He's a fantastic player. It's always a special occasion, with the defending champion coming back on the Saturday and playing all day Saturday as is the tradition. Happy days."
Ronnie O'Sullivan last landed the world title when achieving back-to-back successes in 2012 and 2013, and the five-time champion will face Wallsend cueman Gary Wilson in his opener. Wilson is one of five debutants in the draw.
Wilson, 31, said: "It is a great draw for me. It will be a massive and passionate crowd, millions watching on TV and you couldn't have asked for a better one in many ways.
"I will just be going out to enjoy it and it doesn't bother me that it is a big name. I know what I am capable of and if I play well and score heavily I can cause an upset.
"I like that kind of venue, I think of it like a working men's club like I am used to playing at up in the north-east. A two-table set-up and old guys sitting round in chairs!
"It is a dream to be playing at the Crucible for the first time."
The 17-day tournament runs to May 1, and the champion will collect record prize money of £375,000.