Both teams were already guaranteed a top four finish, and a place in the play-offs, but both were looking for match points to try and secure a possible second pace finish to give them a choice of opposition in the end of season title decider.
And it was the Bandits to made the best possible start, David Bellego and Claus Vissing taking a 1-5 from the opening race to put the visitors in front.
Ex-Bandit Paul Starke won heat two ahead of the returning Matty Wethers, now racing at reserve, and wins for Steen Jensen in three and Matej Kus in four meant Berwick held a slender two point advantage.
Bellego and Vissing did it again in five, both passing Rasmus Jensen off the second bend for another 1-5 and the Bandits found themselves 12-18 in front.
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Kus won again in six, and with Wethers taking third, a 2-4 saw Berwick move 14-22 ahead.
But the Rebels were not about to let Berwick get away with things so easily, and a 5-1 from seven when Steen Jensen fell in second place, saw the home side close the gap to 19-23.
Nick Morris passed both Alex Edberg and Bellego in eight to join Todd Kurtz for another 5-1 in eight, and suddenly it was all square again at 24-all.
By this stage Somerset were getting into the groove and another two 5-1’s saw them open up an eight-point lead of their own - a 16-point swing in four races!
Bellego and Vissing stopped the rot with a shared heat behind Morris in 11, but at 37-29 the Bandits looked as if they might be in trouble.
Wethers and Charles Wright passed each other several times before falling on the fourth lap, Wethers being excluded and a 4-2 saw the Rebels ten in front with only three races remaining.
A 5-1 from Morris and Oliver Allen in 13 guaranteed Somerset the win, and finishing with a flourish they went on to take all three match points, Berwick leaving empty handed.
Team manager John Anderson said: “We made a cracking start and caught Somerset off guard with David Bellego taking two great wins in his first two and Claus Vissing two paid wins with him whilst Matej Kus also weighed in with two victories. But mid-match the home side seemed to visibly regroup and hit back hard and we were left floundering to a degree, despite some hard and exciting racing.”
Somerset: Morris 15+2, Jensen 14+1, Kurtz 8, Allen 7+2, Wright 6+2, Starke 6+2, Brady Kurtz rider rep.
Berwick: Bellego 8, Vissing 7+3, Kus 6, Jensen 5, Wethers 4, Doolan 3, Edberg 1.