Marist College of Athlone produced the biggest shock of the Connacht schools season year so far when they edged past league winners and Cup favourites Garbally College in a tense encounter at Ballinasloe.
Garbally enjoyed huge dominance in the lineouts and overpowered their Athlone rivals in the rucks and mauls, but they couldn't create a try and so were sucker-punched when Ireland U-18 out-half Luke Carty landed a 40-metre penalty to give Marist a 13-12 win.
A superb line break by Jamie O'Keeffe set up Marist's first possession inside the Garbally 22 after 13 minutes and it wasn't wasted as Cian Irwin duly sauntered in for the game's only try.
However, Marist's weakness in the lineout was continually exposed by Garbally's powerful forwards and after trailing 10-6 at the interval, the home side hit the front after 47 minutes, all of their scores coming from excellent Simon Keller penalties.
They failed to add to that tally and were punished when Carty split the posts from just inside the ten metre line with barely five minutes remaining. Garbally tried to respond but Carty again came to the fore when he ripped possession from Dylan Connolly on the try line at the death.
Marist must now travel to Sligo Grammar school on Monday and the pressure was heaped on both sides by Summerhill College, who picked up a 27-5 bonus-point victory over Coláiste Iognáid in Galway.
'The Jes' were already eliminated but offered stiff resistance early on before out-half Jack Keegan broke through for two Summerhill tries before half-time. Cillian Gallagher and Adrian Cummins both crossed in the second half, leaving Summerhill on top of the five team group with two games remaining.
Coláiste Iognáid fans gained some consolation when their junior cup side recorded a 46-0 win over Gallen CS to keep their slim hopes alive.