Haverfordwest showed an early strength to score the first try of the match and an easy conversion.
Tenby pushed on hard, but despite good passing by Ross, Phillip, Ieuan and Curtis, they failed to make the line and Haverfordwest took the chance to score again.
Loui and Rob had Haverfordwest on the go, with Ryan and Deri putting Curtis in position for a long run up the line, only to put a foot in touch.
Haverfordwest scored twice again, despite good defensive play from Ashley, Carwyn, Daniel and Rhys, and added another just before the final whistle.
Tenby found the going hard after only two weeks back after the summer holidays, but will be back as lean, mean, winning machines ASAP. Good luck Vikings.
Team: Loui Fecci, Curtis Hurlow, Daniel Robins, Robert Fairlie, Carwyn Lawrence, Phillip Horsley, Ross Edwards, Rhys Lewis, Ashley Andrews, Ieuan Williams, Ryan O'Neill, Deri Isaac.