By Clive Jones
BBC Sport at the Crucible
Mark King announced his retirement from the game after the 11th seed slipped to a shock 10-5 defeat against Drew Henry.
Henry celebrates his victory
King only played well in patches in a scrappy encounter and was never able to claw back a 6-3 first session deficit.
Henry benefitted from several fortuitous breaks of the ball, but took full advantage as King's game began to unravel.
And the world number 22 held his nerve to win two frames on the black before getting over the winning line with a break of 35.
"It was a scrappy match, but I did what was needed to get through," said Henry.
"In the seventh frame I had a terrible fluke on the pink but you've got to take your chances when you get them."
And the Scot was full of praise for Michaela Tabb who became the first woman to referee at The Crucible.
"Michaela was great," he said. "Hopefully one day she'll get to referee the final. She's a very good referee.
"But I would say that because I won!"
A disappointed King said: "It's just one of those things - sometimes it doesn't go for you.
"In the first frame of the session I was 6-3 down and I got him in a wicked snooker but Drew got out of it by fluking a red in the middle and then he cleared up.
"That just sums my season up really. I thought it might be my turn to have some luck but it was just relentless."
First round result: D Henry (Sco) 10-5 M King (Eng)
71-23 7-54 66-44 89-37 34-70 65-3 61-48 73-37 21-66 64-56 0-85 8-116 66-60 65-56 72-60