Four-time world champion Mark Selby faces first round exit at the Crucible

Mark Selby struggled in the opening session of his first round match against Joe O’Connor (Richard Sellers/PA)

Four-time champion Mark Selby is on the brink of crashing out of the World Championship at the first hurdle after losing the first session of his first round match 7-3 to debutant Joe O’Connor.

Selby, who questioned his future in the sport after losing to Gary Wilson in the Tour Championship earlier this month, was second best against his Leicester rival, who reeled off five frames in a row to leave himself in a commanding position ahead of Monday’s resumption.