Ronnie O'Sullivan will launch the defence of his Dafabet World Championship title against Finland's Robin Hull on Saturday morning.

The draw in London on Thursday lunchtime handed Hull the daunting task of facing the tournament favourite, who will be targeting his sixth world title in Sheffield.

Hull, 39, gave up snooker for three years from 2008 due to a life-threatening virus but has returned, playing sporadically but well enough during the qualifying stages over the past fortnight to earn his second shot at Crucible snooker.

He also got through to the main draw in 2002 and on Wednesday night beat that year's champion, Peter Ebdon, in the final preliminary round.

O'Sullivan has won the last two world titles and is also the reigning Masters and Welsh Open champion.

Of the other likely contenders, China's Ding Junhui will begin his bid for a record sixth ranking title in the same season by playing English qualifier Michael Wasley.

Another English qualifier, Robbie Williams, starts against Australia's 2010 champion Neil Robertson.

Alan McManus landed the draw he wanted as the veteran Scot, who knocked out two-time world champion Mark Williams in the preliminary rounds, was paired with compatriot and four-time champion John Higgins.

Judd Trump starts against Leicester's Tom Ford, Mark Selby has a testing-looking opener against Welsh youngster Michael White, who reached the quarter-finals last year, and 2013 runner-up Barry Hawkins was handed an opener against David Gilbert.

Hull, his country's only snooker professional, responded to the draw by writing on Twitter: "I start on Saturday against R O'Sullivan. Let's go!"

He only stayed on tour this year by virtue of winning the semi-professional European Snooker Championships in Poland last summer and has won little prize-money, but his perseverance has been rewarded by reaching the World Championship and being handed a tussle with the world's leading player.

The six-time world champion Steve Davis is not ruling out a surprise in the top match either, suspecting the likes of Hull may not be cowed by the prospect of facing O'Sullivan.

Davis said: "In some respects a player like Robin Hull has a lot less problems than some of the other players who have been bashing their heads against him and coming up with nothing.

"It seems like a lot of top players have gone into their shell recently when playing against him and so they're not playing their own game. They're certainly in awe of him or in his shadow.

"But the players outside of the bracket, the likes of the qualifiers, will be in awe in some respects but they've got far less to lose than a Ding Junhui or a Neil Robertson or a Shaun Murphy or whoever.

"These lads, their mates think they've got no chance. But they know they can play so they may mentally be in a different situation.

"Of course when you're out there and you're sitting in your chair and Ronnie O'Sullivan is making light work of difficult situations, it may be another story.

"But Robin Hull is a great all-rounder and a class act. If he gets off to a good start - and a good start is always important - then who knows?"

Davis also knows it could go horribly wrong for the Crucible newcomers, adding: "If you're ever going to collapse as a snooker player, that first round is where it can all go wrong but it's also where your dreams can unfold too."

Davis suspects this could be the year that 27-year-old Ding finally fulfils his potential on the World Championship stage.

A serial winner of major tournaments elsewhere, Ding has seemed to find the pressure of the World Championship overwhelming, reaching only one semi-final in seven visits.

"With Ding Junhui, even though possibly we've had times when he's not played at his best against Ronnie O'Sullivan this season, I think he's come of age," Davis said.

"This may be his best chance and he may be ready to win the World Championship this year. He may do it in style."

Draw for the first round of the Dafabet World Championship, starting on Saturday at the Crucible:

Ronnie O'Sullivan v Robin Hull

Joe Perry v Jamie Burnett

Shaun Murphy v Jamie Cope

Marco Fu v Martin Gould

Barry Hawkins v David Gilbert

Ricky Walden v Kyren Wilson

Mark Davis v Dominic Dale

Ding Junhui v Michael Wasley

Mark Selby v Michael White

Ali Carter v Xiao Guodong

John Higgins v Alan McManus

Stuart Bingham v Ken Doherty

Judd Trump v Tom Ford

Stephen Maguire v Ryan Day

Mark Allen v Michael Holt

Neil Robertson v Robbie Williams