In a game played in glorious sunshine, the boys from Threadneedle Road emerged victorious after a very competitive encounter between two equally matched teams.
It was St. Mary's who opened the scoring after eight minutes with a penalty. Emil Hernon scored a penalty to even up the scores after 15 minutes.
A superb individual try again from Hernon saw Colaiste Einde go in at half-time leading by 5 points. An Andrew Rogers try, soon after the restart, left the Salthill youngsters 15-3 in front.
The boys from Ballygar produced an excellent fight back late on bringing the score to 15-11 and with a few minutes on the clock it looked like they would get the crucial score.
However, a fantastic defensive display saw Colaiste Einde hold out for an historic victory.
The RBS 6 Nations and Triple Crown trophies were on hand and both teams were delighted to get a chance to be photographed with them.
The RBS 6 Nations trophy and Triple Crown will be on tour throughout Ireland over the coming year and you can keep up to date with all the places visited on our Grand Slam Map or on www.irishrugby.ie/grandslam.