Both sides started quickly, Carmarthen’s James Dixon giving his side an early lead with a penalty before Richard Powell levelled things up with.
Powell should have increased the Bedwas lead after eight minutes. A quickly taken Bedwas tap penalty was illegally stopped by No 8 Andy Thomas who was despatched to the sin bin for not retreating 10 metres but Powell’s kick into the wind went wide.
Both sides’ defences were working hard and good pressure from the visitors saw Dixon slot a further penalty. Bedwas prop Dan Preece was then sin binned but Dixon’s penalty went wide. Neither side could find space for a try and although Dixon added a further penalty goal, the half petered out with neither side looking like crossing the white wash.
With the wind behind them for the second period, two Powell penalties saw the home side level before a third penalty on the hour saw Bedwas ahead for the first time.
Carmarthen hit back when pressure eventually saw the Bedwas line broken and Rheon James crossed under the posts with Dixon adding the conversion.
But Carmarthen were caught offside from the restart and Powell added the penalty to reduce the arrears to 15-16. At this stage a Bedwas win looked unlikely.
But Carter, who was introduced in the 79th minute, latched onto a great pass from skipper Phill Sargent and galloped away from the covering defence to score with his first touch. Powell added the conversion to push his side further clear.
There was still time for Carmarthen to try to win the game but their attempts to run the ball from two late penalties were countered by the Bedwas defence.