Doherty, the 25-year-old Dubliner, was beaten 10-7 by Mark Davis, aged 22 from St Leonards in Sussex, in a match in which the more fancied player under-performed spectacularly. Wattana put up more of a fight against the 29-year-old Yorkshireman Gary Wilkinson, but eventually went down 10-8.
For Davis, ranked 65th in the world, this was easily the best result of his career and helped wipe out the memory of the defeat he suffered in the first round last year, his only other appearance in the event, when he led 6-3 against Terry Griffiths but went on to lose 10-7.
There was a moment against Doherty when Davis, from 9-6 up, was pulled back to 9-7 and looked as if he might let victory slip from his grasp again. But showing barely a trace of nerves, he came through in the end with room to spare. "I never thought I'd lose," he said, putting him in a very select group indeed.
Doherty, after all, had the talent to be a contender for the title. He reached the quarter-finals here last year, losing to Jimmy White, and in September beat Stephen Hendry to retain his Regal Masters title. But he has lost his way in recent months, and it showed in a fitful performance which could cost him his top-eight ranking and the lucrative opportunities that go with it.
Doherty said he played so badly it gave Davis confidence, which was true up to a point. But Davis has had his own problems this season, having suffered with his wisdom teeth in September when he embarked on the five- match qualifying process which brought him to Sheffield.
So the erratic form shown by both men was not surprising, and there was only one break higher than 46 all day. That was the 85 with which Doherty, trailing 5-4 overnight, brought the scores to 5-5, and the signs were that he was about to take control. But it didn't happen. Davis now plays his stablemate Peter Ebdon, who beat Rod Lawler 10-2, having led 8-1 overnight.
Wilkinson, ranked 22, made similar progress to Davis. He also resumed with a 5-4 overnight lead, dropped the first frame of the day, and the second, but then dug in. The 15th frame was crucial - a shade under 35 minutes' worth of attrition which left the methodical Wilkinson 8-7 ahead, and although Wattana had a little left to give it wasn't enough.
The Crucible audience had to wait for Ronnie O'Sullivan's match with Dave Harold to see snooker at its most expansive. In establishing a 7- 2 lead to take into the final session this morning, O'Sullivan had two century breaks, one of them, of 112, only brought to an end after he had potted 14 reds and 14 blacks and had a 147 in his sights.
There is a wonderful ease about O'Sullivan, and between him and his fellow 19-year-old John Higgins, who begins this afternoon against Alan McManus, there is a distinct possibility that the championship will see its youngest ever winner this year.
The first second-round match to be decided will be between Stephen Hendry, who on Friday began his title defence by beating Stefan Mazrocis 10- 3, and Tony Drago of Malta. Drago yesterday completed a 10-2 win over Yorkshire's Paul Cavney.Reuse content