BY HIS OWN admission, Joe Swail modelled his snooker technique on the irrepressible early skills of Alex Higgins. But it was their shared Belfast strength of spirit which became the key factor in Swail's outstanding quarter final victory over Ronnie O'Sullivan in the £190,000 Benson and Hedges Irish Masters tournament at Goffs yesterday.

It was the first match of this year's event to go the full distance of 11 frames, and Swail finished very much the stronger to win by 6-5. "I'm going to miss the Grand National," he said in mock complaint, as a reference to a second successive semi final appearance here, starting at 1.0 pm tomorrow afternoon. On his debut 12 months ago, the Ulsterman lost by 6-3 to Stephen Henry in the last four.

Though he has failed to qualify for the World Championship, Swail's solid form this season is reflected in an improvement from 19th to 12th in the provisional rankings. O'Sullivan, on the other hand, has been heading grimly in the opposite direction, sliding from third to a provisional eighth, largely through a crippling lack of confidence.

Indeed the situation yesterday afternoon might have been Sheffield's Crucible Theatre as he said. This is a big tournament and there was so much pressure out there, particularly in the last flame. It's the hardest I've tried all season, but it wasn't enough. Joe did well. I can't take anything from him.

In fact Swail did so well that he came from 4-2 and 5-3 down to take the match by winning the last three frames. And we shouldn't have been surprised at his admirable tenacity, given that he was 4-2 behind in a first round meeting with John Parrott on Monday, when he went on to win by 6-4.

A fine break of 103 gave O'Sullivan the sixth frame for a lead of 4-2. But Swail responded with a break of 101 in the next. Then the Londoner extended his lead once more in a 36 minute eighth frame in which the referee decided on a re-rack after the players had got bogged down with most of the reds gathered around the black on the lip of a corner pocket.

Breaks of 43 and 18, which contained some exemplary long potting gave Swail the ninth frame. In the past, O'Sullivan could have been criticised for some rather reckless play under pressure, but it was to his credit that he persisted with a more careful approach on this occasion. Still, he continued to struggle while the Irishman was winning the 10th, this time with breaks of 64 and 24. So the match had gone down to the wire.

Effectively, the match hinged on O'Sullivans ability to clear the colours after taking a black off the last red. But he was always going to have problems with the blue which was on a side cushion, midway between the middle and corner pockets. As it happened he missed the difficult pot and the ball ran up to the far end of the table before coming to rest over a baulk pocket.

Swail claimed afterwards that he was extremely nervous at that stage. But he successfully hid his, discomfiture to take blue and pink for the match. "The crowd were great, but you're always afraid of making mistakes in front of that sort of support, said the 26 year old, who hails from the Market's Area of Belfast.

He went on Early in my career, I modelled my game on Alex Higgins, with the result that, I became very attack conscious. Nowadays, however, I try to be more aware of safety, though I still like to attack when the occasion presents itself."

Later in the day, Peter Ebdon failed to surmount the first hurdle in his attempt to emulate the achievement of such notables as Steve Davis and Jimmy White by successfully defending the title. As had happened in the afternoon, the match went the full 11 frames before the champion lost by 6-5 to the world number eight Darren Morgan.

In the public preamble to their clash, it became clear that relations between Ebdon and Morgan were decidedly cool. Indeed they barely looked at each other when shaking hands. All of which stemmed from the Welshman's mischievous reaction when beating Ebdon in the British Masters at Wembley last month.

On that occasion Morgan was excessively demonstrative in his victory celebration, aping the established behaviour of his emotional opponent. Ebdon took exception and it seemed to give an edge to his determination last night when he had a break of 100 to take the second frame and a superb total clearance of 138 in the third.

Still, Morgan managed to stay in touch, notably by stealing the fifth after Ebdon had missed a cut on the blue into a centre pocket when set up for a fairly rudimentary clearance. And by the end of the eighth, in which the Welshman had a clearance of 62 to the blue, they were deadlocked at 4-4.

And he had to come back once more to level at 5-5 with a clearance of 57 before gaining a deserved victory in a tense, climactic frame. After Ebdon had gone into an early 31-0 lead, the Welshman worked his way back into contention with breaks of 29 and 19 and eventually forced a concession on the blue. He meets Swail tomorrow afternoon in the first semi final.