Half-backs Jonathan Sexton and Matt D’Arcy accounted for 15 points as St Mary’s secured their first away win in the AIB League since October.
Scrum half D’Arcy scored a third-minute try as Mary’s, with Ronan Doherty soon adding a second touchdown, foraged into a 15-6 half-time lead.
Winger Eamonn Fitzgerald landed three penalties in all for Belvo but the hosts, who included Leinster winger Simon Keogh, failed to convert a series of try-scoring chances, leaving D’Arcy to seal victory with a late try.
Scorers:
Old Belvedere: Pens: Eamonn Fitzgerald 3.
St. Mary’s College: Tries: Matt D’Arcy 2, Ronan Doherty; Con: Jonathan Sexton; Pen: Jonathan Sexton.
