The Gortnor Abbey squad who defeated the All-Ireland champions in Glencar.
The Crossmolina students then made hay in the second half, kicking 1-11 to 1-1 and finishing off with a wonder goal from midfielder Kobe McDonald to secure victory.
Gortnor Abbey adapted best to the conditions and their cast of exceptional shooters produced a slew of impressive two point scores at important times to take charge of the game.
The crucial score of the opening half arrived after 20 minutes when a McDonald free kick dropped short and was pounced on by Rory Coyne who fired it into the net. That kept the boys in black well in touch as they changed ends for the second period.
The second half opened promisingly for St Clare's with Karl Gethins kicking a point from close range after a shot from Ronan Fox was held up by the wind and fell dangerously around the square.
However, Gortnor Abbey were building a head of steam and had faith in their shooters, as Mark Sheerin, McDonald and Lorcan O'Donnell soon had the scoreboard ticking nicely.
St Clare's were struggling to retain the ball in the face of mounting pressure being applied by a Gortnor Abbey team that had their tails up. That said, the Leitrim boys got a huge boost when a Ronan Fox free kick effort from near the sideline ended up in the net.
The goal gave them a lifeline and made it a two-point game - but that is as close as they got.
McDonald sliced over a brilliant two-pointer and then scored a stunning goal. Running through the middle of the routed defence with support runners alongside him, he looked up and decided to have a go himself and popped a rocket of a shot into the top left corner from all of 30 metres.
He wheeled away with his teammates in tow, certain they had booked their place in the Connacht semi-final.
A full report will be carried in Tuesday's Mayo News.
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