CWM'S Mark Williams (pictured) will resume one of snooker's fiercest rivalries at the £600,000 LG Cup in Preston today with controversial Aussie Quinten Hann determined to cause an upset.

Hann takes on the world number one, who has not lost his opening match in a world ranking event since the Regal Scottish Open of February 1998. Since then, the Welsh left-hander has cleared his initial hurdle on 30 consecutive occasions.

But Hann, talented, unpredictable and with no respect for reputations, is looking to beat him for the third time in four meetings. It is also fair to say the pair are not the best of friends.

"I've not spoken more than 10 words to him in my life," said Hann, after scoring a 5-3 win over Nottingham's Michael Holt in the previous round. "I don't usually get worked up for matches but I will for this one. There's a bit of needle."

Many believe Williams, without a title since he lifted the Grand Prix trophy in Telford 12 months ago, could be vulnerable to a rare early exit.

Williams, who admits his form is "diabolical," recently joked: "The only person I could beat at the moment is Stephen Hendry," clearly referring to the slump being experienced by the seven-times world champion.

Although Williams squeezed past him 10-9 in the first round at the Crucible in 1998 - after leading 9-4 - Hann knows what is required to get the better of the player regarded as snooker's most deadly long ball potter.

Hann beat him twice in 1997 at the German Open and Thailand Open, and has the necessary self-belief to send Williams even deeper into the doldrums.