World Championship draw: Ronnie O'Sullivan plays Marcus Campbell
- The Crucible Theatre, Sheffield
- 20 April-6 May
- Live on BBC Two, Red Button and online on the BBC Sport website, mobile and BBC Sport app. Updates on BBC Radio 5 live
Four-time winner Ronnie O'Sullivan will face Marcus Campbell in the first round of the 2013 World Snooker Championship.
O'Sullivan, 37, has not played in a major event since winning last year's title, but returns to action against Campbell, the world number 27.
World number one Mark Selby is up against Matthew Selt, Neil Robertson plays Robert Milkins, while Judd Trump meets Welshman Dominic Dale.
O'Sullivan will play in the first match at the Crucible on Saturday, 20 April.
He defeated Ali Carter 18-11 in the 2012 final but then refused to sign the players' contract for the current season, an act that made him ineligible to play in competition.
However, in February he announced he would play in this year's World Championship, a tournament he would not need to qualify for as he was the defending champion.
But he faces a tough first match against Scotland's Campbell, who reached the semi-finals of the 2012 Wuxi Classic in China.
Sam Baird, 24, has had to win four qualifying matches to reach this stage and is one of six players who will be making their Crucible debuts.
Baird, the world number 83, is the lowest ranked player left in the competition and plays Premier League champion Stuart Bingham, while Jack Lisowski, Michael White and Ben Woollaston face Barry Hawkins, Mark Williams and Carter respectively.
Thailand's Dechawat Poomjaeng will be against Stephen Maguire, and Scotland's Alan McManus, playing at the Crucible for the first time since 2006, is Ding Junhui's opponent.
There is a repeat of the 2006 final as Graeme Dott, who won that title, takes on 2002 champion Peter Ebdon, while two-time World Championship runner-up Matthew Stevens plays former Grand Prix winner Marco Fu.
The World Snooker Championship is played over 17 days at the Crucible in Sheffield with the final being completed on Monday, 6 May.
WORLD CHAMPIONSHIP FIRST ROUND
(Seeded players are in brackets)
(1) Ronnie O'Sullivan v Marcus Campbell
(16) Ali Carter v Ben Woollaston
(9) Stuart Bingham v Sam Baird
(8) John Higgins v Mark Davis
(5) Shaun Murphy v Martin Gould
(12) Graeme Dott v Peter Ebdon
(13) Matthew Stevens v Marco Fu
(4) Judd Trump v Dominic Dale
(3) Neil Robertson v Robert Milkins
(14) Ricky Walden v Michael Holt
(11) Mark Williams v Michael White
(6) Stephen Maguire v Dechawat Poomjaeng
(7) Mark Allen v Mark King
(10) Ding Junhui v Alan McManus
(15) Barry Hawkins v Jack Lisowski
(2) Mark Selby v Matthew Selt