Defending champion Luca Brecel has been battling a mystery illness in the build-up to his return to the World Snooker Championship on Saturday.

A nosedive in form and the so-called ‘Crucible curse’ – in which no first-time winner has ever managed to retain the title – are not the only issues afflicting the 29-year-old, who faces a tough opener against former semi-finalist Dave Gilbert.

“I’ve lost my voice a couple of times and I’ve had headaches, a bit like Covid,” said Brecel. “It’s been coming and going ever since the tournament in Saudi (in March), but it’s too big not to play in this one.”

Despite his stunning breakthrough win last season, Brecel heads to the Crucible with arguably the lowest expectations of any returning champion, having reached a solitary ranking event quarter-final this season.

And the Belgian is more than happy to accept the underdog status, adding: “I’m up against a very good player and Dave is probably the favourite to beat me, so it’s a nice challenge.”

Brecel claimed he never practised in the build-up to his famous win last year, in which he edged Ricky Walden in a final-frame decider in the opening round before going on to seal epic back-to-back wins over Ronnie O’Sullivan, Si Jiahui and Mark Selby.

This year he has at least been putting in the hours on the practice table, and says that having achieved his lifetime goal he is able to approach the Crucible with a more pressure-free mindset.

“I remember when I played Ricky last year in the decider I was really nervous at 9-9, and if goes to 9-9 now I won’t feel any nerves,” added Brecel.

“There’s nothing higher than winning the worlds and when you have that goal you always put pressure on yourself, and if you don’t get close to that goal you get frustrated.

“It’s much easier now. I don’t have that any more. I’ve won it before so it’s just about trying to be a better payer and a better person. That’s my goal now.

Brecel and Gilbert will play to a finish on the opening day, while Judd Trump gets his quest for a second title under way against Hossein Vafaei, and two-time finalist Ali Carter starts against Stephen Maguire.