Retour
Pennar had won the last time the sides met last season, while Tish had won the other game.
Tish took the lead in the 17th minute on Saturday as Ieuan Hawkins set up Joel Mills to score.
Mills then grabbed his second goal of the game, and his fourth of the season, 10 minutes before half time, leaving Pennar with work to do to get back into the game.
In the second half, Pennar looked to get a goal back but were just unable to do so.
And with just over an hour played, the points were all but secured for the visitors when Conner Willis put the ball into his own net.
Tish saw the game out to seal a welcome win which moves them out of the bottom two.
On Saturday, November 7, the sides are in action in the second round of the West Wales Cup.
Pennar Robins visit fellow Pembrokeshire side Kilgetty.
St Ishmaels are at home as they host Carmarthenshire League side Drefach.
The sides are next in league action on November 14 when Tish visit Carew and Pennar visit Milford United.