This was the first of two games before Christmas that Stewartry were looking to win and move up the league table for a top-five finish at the end of the 2018.
The Blacks started well and were rewarded with a penalty for a high tackle in only seven minutes. Leading points scorer Craig Mosey kicked the ball between the posts for a 3-0 lead.
Cumnock changed their tactics after a poor start. They kicked for position putting Stewartry under pressure and after three phases Cumnock scored in the corner, 5-3 Cumnock.
Minutes later Stewartry were penalised for hands in a ruck and Cumnock added a penalty score 8-3.
Stewartry took play back into the Cumnock 22 winning a lineout and driving over for a try as hooker Kieran McGuire peeled of the back to score. Mosey added the conversion. 10-8 to Stewartry.
An injury to captain and fullback John Fingland saw him go off and Stewartry rejigged the back line Scott Milligan going to full back and Fergus Donaldson making his debut for the Blacks on the wing.
Cumnock again kicked long into the corner, turned Stewartry over and went through a number of phases to score out wide. The conversion missed and Cumnock led 13-10 at half-time.
The second half played out much of the same as both teams battled hard. A quickly taken free kick by scrum half John Picken saw the forwards set up Danny Boyd for a second try. The conversion missed. 15-13 Stewartry back in the lead.
There was a bit of a mix up in the Stewartry goal area, Cumnock were quickest to reach the loose ball and score a third try 18-15 to the locals. Cumnock kept the pressure on but in the end a penalty score was all Cumnock had to show for their effort. 21-15.
With only five minutes to play Stewartry needed another score. The Blacks stayed patient and worked a number of phases, retaining possession and driving hard at the line. Four penalty awards did not bring a penalty try to Stewartry, before prop Mick McCulloch drove over at the posts for his first ever try for the Blacks. Mosey added the conversion 22-21 to Stewartry.
The win puts Stewartry up to fifth and they are looking to retain it with another win at home to Cambuslang this weekend ko 2.00pm at Greenlaw.