Ken Doherty will figure in the semi-finals of a world ranking tournament for only the second time this season at the £280,000 Thailand snooker Masters in Bangkok.

The world champion, who has not lived up to his expectations so far during the 1997/98 campaign, ensured progress with a 5-3 victory over Alan McManus yesterday.

But Doherty, edged 5-4 by the tough Scot in the final of the competition two years ago, was made to sweat before crossing the line.

Doherty, a 5-4 winner over local hero James Wattana in the last 16, this time benefited from a fine start as he quickly established a 4-1 advantage.

A 79 break in the first frame opened the floodgates, he added a run of 50 in the second, and after McManus had jawed an elementary red to a top corner pocket in the fourth, Doherty stepped in with an 89 clearance.

McManus lost a scrappy fifth frame as well, but Doherty, whose other ranking event semi-final appearance of the season came at the German Open in December, threw him a lifeline by going in off a safety shot early in the next.

A 64 break helped McManus stay alive, he also controlled the seventh and was set to carry the contest to the wire when given a clear-cut scoring opportunity in the eighth.

McManus, unusually prone to unforced errors throughout, missed a simple pink to a middle pocket, though, and Doherty's composed 35 break left the Scot requiring snookers.

"I'm delighted and relieved to get through, because I was genuinely worried about being given a taste of my own medicine," admitted Doherty. "I never fully settled down, but this is a great result."

Doherty now meets Stephen Hendry in a repeat of last year's World Championship final while, in the other semi-final, John Parrott takes on Anthony Hamilton, a surprise 5-2 conqueror of Nigel Bond earlier yesterday.