With a game tied at 26-26, Ian Costello saw a penalty for UL Bohs come back off the upright and the contest seemed certain to end level. But with virtually the last kick of the game, Costello dropped a goal to secure a famous win.
Bohs led 13-0 after 12 minutes, Costello dropping a goal, landing a penalty before following up with a try that he also converted. Alan Purcell got Garryowen off the mark after 25 minutes, but Costello replied with a penalty and then Keith Matthews flew in for a superb try which Costello converted to make it 23-3.
But Garryowen clawed their way back with a try by Paul Nevilleand a penalty by Purcell to trail 23-11 at the break. Garryowen backed by the breeze, took control in the second half and tries from Pat Humphries and Purcell made it 26-21.
A second Neville try ten minutes from time tied the game until Costello's dramatic drop goal.
Shannon 25 Dungannon 18 Cork Con 21 Harlequins 27 Galwegians 16 Clontarf 34 UCD 24 Buccaneers 34 Ballymena 77 Terenure College 0