New Bargoed head coach Aled James suffered a 25-7 defeat at Aberavon in his first game in charge.
The hosts exacted their revenge on Bargoed, who won the reverse fixture at Bargoed Park in October – the last time the Bulls won a league fixture.
The defeat sees Bargoed stay in 15th place in the Principality Premiership table, 19 points behind Bedwas with two games in hand.
Aberavon centre Joe Gage opened the scoring in the 18th minute to give his side a 5-0 lead on a cold, wet and windy afternoon.
A huge punch up saw both Bargoed captain Rhys Morgan and Aberavon skipper James Garland sent to the sin bin for ten minutes.
Rhodri Cole scored the penalty that followed to give the hosts an 8-0 lead.
With a minute left of the first half, Aberavon kicked straight to the Bulls and centre Ashley Norton set up back-rower Calum Davies to score Bargoed’s only try of the game.
Outside-half Josh Prosser converted the try to reduce Aberavon’s lead to jut one point at half time.
The two captains returned to the field after the break following their earlier yellow cards.
Aberavon were awarded a penalty try in the 51st minute, but the game was delayed while Bargoed winger Jordan Purcell was stretchered off after an injury.
After play was resumed, Garland added the conversion to put Aberavon 15-7 up.
Garland later added a penalty to extend his side’s lead to 11 points with ten minutes left.
Ill-discipline struck Bargoed once again in the 76th minute, with replacement prop John Lavender being sent to the sin bin.
Aberavon sealed the win when No8 Andrew Waite intercepted from a Bargoed throw-in to run in for a try in the sixth minute of added time. Garland was successful with the conversion to seal a 25-7 victory.
Bargoed dug in deep for four more minutes of added time to prevent their opponents from scoring a fourth try and earning a bonus-point win.
The bulls return to Bargoed Park on Friday, March 8 to take on North Wales outfit RGC 1404.