Although Narberth saw their first team fixture at home to Glamorgan Wanderers called off because of Saturday's downpour, it didn't stop their second string making the journey to play Penlan.
Conditions were hardly ideal for good rugby, though, with the torrential rain and mist making life distinctly unpleasant for both sets of players.
Nevertheless, it was Narberth who started the brighter and by half-time they held a slight 6-3 advantage thanks to two Scott Penny penalties.
After a good talking to at the interval, however, Penlan upped their game in the second period to notch a further 14 points, with only seven in reply from the Athletic.
Narberth's try scorer was flanker Dafydd Bowen, with Penny adding the extras with a successful conversion.
Fullback Shane Higgon was nominated Narberth's man of the match.