Snooker: Two-time champion Mark Williams knocked out by debut boy Michael White

Michael White, one of six Crucible debutants, sprung a major upset here at the World Championship in Sheffield yesterday when he knocked out Mark Williams, the two-time world champion.

White beat fellow Welshman Williams 10-6 in their first-round tie and in doing so the 21-year-old from Neath clinched the biggest victory of his blossoming career.

"I'm over the moon, it's hard to take it all in," said White, the world No 41. "To win at the Crucible is something you dream of, but to actually do it is incredible. It's [the Crucible] an unbelievable place to play at, but I was really pleased with the way I coped with it all.

"To beat Mark means everything to me. I always looked up to Mark as a kid growing up. It was a privilege to play him. I'm a lot more experienced than when I turned professional four years ago, my game is where it needs to be. Hopefully I can put in another performance like that in the next round."

White led 4-1 in the match, was pegged back to 4-4, but held a slender 5-4 overnight lead when the apprentice and master returned to conclude their best-of-19 frame encounter.

It was White who showed experience beyond his young years to dominate with breaks of 65, 72, 90 and 96 in winning five of the next seven frames. He next faces either Scotland's Stephen Maguire, the former UK champion, or Thailand's Dechawat Poomjaeng.

Former world champion Graeme Dott returns today 6-2 up on Peter Ebdon in a repeat of their 2006 world final, while fellow Scot John Higgins will have to stage a comeback having fallen 6-3 behind after the opening session of his first-round match with Mark Davis.

Stephen Hendry, the seven-times world champion, believes Ronnie O'Sullivan, who defeated Marcus Campbell at the Crucible on Saturday, must knuckle down to stand any chance of eclipsing his impressive record of world titles.

Hendry remains the most successful player on snooker's greatest stage but he knows O'Sullivan has the potential to win three more world crowns, having made his comeback after a 12-month break at this year's championship.

"If [Ronnie] has got ambitions to beat my record he really needs to knuckle down," said Hendry. "He just has to have one objective over the next few years. He has got the game, but whether he has got it in him to focus and dedicate his life we will have to see."

Barry Hearn, the World Snooker chairman, has lodged a complaint with the BBC after they pulled the plug on coverage of O'Sullivan's first-round match just before it was due to finish. BBC2 switched to a repeat of Some Mothers Do 'Ave 'Em.

Hearn tweeted: "Sorry to all snooker fans for the poor BBC coverage last night. Letter of complaint sent to BBC today."