Tries from Josh O'Connor and Cian McCann weren't enough to secure victory in Dubarry Park.
It was another agonising defeat in the AIL for Buccaneers over the weekend.
Paul Byrne's side found themselves trailing 21-8 at home to Naas on Saturday when the Kildare side were reduced to 14 men after sustained pressure from the Buccs.
Cian McCann then crossed the whitewash for the Athlone club to set up a grandstand finish in Dubarry Park.
Naas withstood the late pressure to win the game on a final scoreline of 21-15 and consigned Buccaneers to their ninth loss of the season.
Coverage with thanks to Reynolds Commercials Athlone, new CVRT centre opening soon offering testing for light and heavy vehicles. Reynolds Commercials – Service – Quality – Reliability. Reynoldscommercials.ie
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