Ken Doherty's purple patch continued in Bangkok yesterday but only after he survived an early scare in his opening Thailand Masters outing.

Doherty, runner-up in the Benson and Hedges Masters and winner of the Rothmans Malta Grand Prix during February, safely reached the quarterfinals with a 5-3 victory over little-known Scot John Lardner.

But when world number 72 Lardner impressively built a 3-0 advantage a major shock appeared on the cards in the £270,000 event and Doherty's hopes of back-to-back "ranking tournament successes" were in grave danger of being extinguished.

"It was a bit of a crisis," admitted the 1997 world champion. "Thankfully I got my head together in the nick of time.

"If I'd lost it would have been heartbreaking because, when you're on the top of your game you've got to try and make the most of it."

Doherty, beaten in only one of his last 10 matches, added: "The way John started I was thinking about being on the first flight back to Dublin. That would have been a swift return to earth after what happened over the past few weeks."

As the match wore on Doherty grew in confidence despite damaging the tip of his cue while Lardner, who had never previously figured in the last 16 of a ranking event, let alone appeared in a quarter-final, began to struggle badly.

Doherty, in control throughout the second half of the contest, now faces Billy Snaddon, the surprise conqueror of Jimmy White.