World Snooker Championship: James Cahill wins first frame against Ronnie O'SullivanBetfred World Snooker ChampionshipVenue: Crucible Theatre, Sheffield Dates: 20 April-6 MayCoverage: Watch live on BBC One, BBC Two, Red Button, iPlayer, Connected TV, BBC Sport website and BBC Sport app.
Tournament favourite Ronnie O'Sullivan trails gutsy amateur James Cahill 5-4 after a shaky opening session in their World Championship first-round match.
Debutant qualifier Cahill, the first amateur to play at the Crucible, settled immediately to go 1-0 up.
He then trailed the five-time champion 2-1, 3-2 and 4-3, but came back on each occasion and pinched frame nine against an increasingly rattled O'Sullivan.
Four-time champion John Higgins beat Mark Davis 10-7 to progress.
Scotland's Higgins was in impressive form to see off his fellow veteran in an intriguing match.
But the true drama came between O'Sullivan and the 23-year-old Cahill, who showed great resilience to stay in the match when many would have crumbled.
A confident start saw him win the opening frame with a brilliant pot on the black.
The 43-year-old 36-time ranking event winner responded, pouncing on Cahill mistakes to go 2-1 ahead with breaks of 51 and 86.
Cahill kept his composure with a fine 71 to level at the mid-session interval and the pair then exchanged frames.
O'Sullivan's performance was becoming increasingly error-strewn and he was fortunate to fluke a snooker and steal frame seven, but Cahill once again showed his backbone, winning two tense frames for a first-session lead.
Analysis
Six-time world champion Steve Davis on BBC TV
It was probably the worst session of snooker Ronnie O'Sullivan has played this season.
I just think he is playing too quickly. It's as if he wanted to get out of there. It didn't look like he was enjoying being there.
James Cahill's attitude has been brilliant. He has played with rhythm and confidence.
Higgins holds off Davis fightback
Last year's runner-up Higgins fended off a spirited effort from the 46-year-old Davis to reach the second round.
Higgins, making his 25th consecutive Crucible appearance, led 6-3 overnight only for his advantage to be cut to 7-6.
But two superb tons helped him get to within one frame of the victory target and he closed out the win in frame 17.
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