Michael Holt faces a do-or-die bid to remain on the World Snooker Tour after slumping to a 4-2 defeat to Zhao Jianbo at event two of snooker Q School in Sheffield. The former Shoot Out winner suffered a shock 4-3 defeat in the second round of event one to 17-year-old amateur Nattanapong Chaikul last week and could not stave off another premature exit to 18-year-old Zhao in the fourth round. Ad/> Holt – who joined the professional circuit in 1996 – faces the end of his 26-year stay on the main circuit unless he can claim one of the final four tour cards available at event three of Q School.