Most recently, the 2023 champion Luca Brecel lost in the first round of the 2024 World Snooker Championship.
Several world champions successfully defended their first title in the pre-Crucible era; the last to do so was John Pulman in 1964.
Of the 19 players to have won their first world title at the Crucible Theatre, seven lost in their first match as defending champion: Terry Griffiths in 1980, Steve Davis in 1982, Dennis Taylor in 1986, Graeme Dott in 2007, Neil Robertson in 2011, Stuart Bingham in 2016 and Luca Brecel in 2024.
No player in the modern era (post-1969) has successfully defended a first world title, even before the tournament was staged at the Crucible Theatre.
All three players subsequently won the championship at the Crucible for the first time, but then fell to the "curse" when they failed to successfully defend the title the following year.