Whitland's cause was not helped by match referee Elwyn Marfell-Jones disallowing two tries, one in each half, which seemed to all supporters at the ground, fair scores.
Apart from this, it was a lack-lustre performance, with only the odd spark or two being shown by Alun Davies and Huw Devonald in the front row, second row Raff Williams, back row Phil Morgan, Lee Glanville and Matthew Hughes in the centre, and Luke Marsh on his return from Llandovery.
In the first half, Whitland played into a very strong breeze, but turned round only three points down, which came from a penalty by outside-half Rob Townsend, who had earlier missed three attempts. Whitland's Aled Davies was also unsuccessful with his only attempt of the first half.
Three minutes into the second half, Waunarlwydd extended their lead when left winger Alan Pope went over for an unconverted try.
Aled Davies had a chance to reduce the deficit with a penalty soon after, but was again off target with his kick.
From the resulting drop out, Luke Marsh gathered and lined up a drop goal, which just faded to the right of the posts.
Twelve minutes later, he took over the kicking duties, being unsuccessful with his first attempt, but landing the second after 23 minutes, to give the Borderers their first and only points of the match.
Try as they might, Whitland failed to cross the home line, although it did seem that Lee Glanville had brought the scores level, after a powerful run, only to be penalised for a double movement.
Waunarlwydd sealed the three points when replacement winger Paul Davies went over for his side's second unconverted try of the afternoon. Team fielded: Will Davies, Dion Thomas, Lee Glaville, Matthew Hughes, Ali Bowen (Colin Jones), Aled Davies, Luke Marsh, Gareth Williams (Alun Davies), Huw Devonald, Richard Smith (Andrew Morillo), Raff Williams, Aled Evans (Carwyn Davies), John Bowen, Phil Morgan, Randall Williams, capt.
Whitland 2nd XV 18 pts. Llangennech 6
Whitland played Llangennech in the second round of the Poly Pipe Civils League Knock Out Cup and moved through to the next round after a convincing win by 18 points to six.
Whitland scored two tries through outside-half Shane Morgan and centre Wayne James, with winger Ross Michael kicking two penalties and adding a conversion.