Two second half tries were enough for the province to turn it around.
Leinster made it back to back wins in the Champions Cup over the weekend.
Leo Cullen's side secured a 23-15 victory over Leicester Tigers away from home, with thanks to second half tries from Jamison Gibson-Park and Dan Sheehan.
Athlone's Robbie Henshaw started and played the full 80 minutes.
It's two wins from two for the province following their 17 point win at home to Harlequins last weekend.
Cullen says a win was important:
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