|2017 World Snooker Championship|
|Venue: The Crucible Theatre, Sheffield Dates: 15 April - 1 May|
|Coverage: Watch live on BBC TV, BBC Red Button, Connected TVs, online and app|
Ali Carter says a "nightmare" first session was the reason for just his third World Championship first-round exit of his career.
The world number 10 was beaten 10-7 by Graeme Dott - the first time Carter has failed to make the last 16 since 2006.
Two-time finalist Carter told BBC Sport: "I lost it in the first session.
"Graeme is a tough opponent. It was a bit like watching Alex Higgins play - you think he's going to miss at any moment but he keeps knocking them in."
Carter, whose 15 Crucible appearances have come consecutively since he first qualified in 2003, trailed 4-0 after a disastrous start.
But he battled back to 6-3 and then 8-7, before the 2006 champion closed out victory.
Carter added: "It's hard to play against him because he is good at winning all the scrappy frames.
"By the breaks I looked the better player but it wasn't meant to be. I was just fractions out all of the time from being perfect.
"The first four frames summed it up - I had a complete nightmare. I should have won at least three of them and the score ends up 10-7 to me.
"I just didn't make the most of my chances and that came back to haunt me."
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