The first half had been even, the sides tied at 6-6, when, on the half hour, Hatherell was sent off for a tip tackle. Scott Lyle scored his third penalty, against two from Colin Sturgeon, and Ayr led at the break.
The second half was virtual one-way traffic but it took Ayr until the final eight minutes to make their advantage pay. A penalty try, after Marr illegally halted an advancing Ayr five-metre scrum, gave the champions breathing space, before Lyle’s fourth penalty made the game safe with five minutes left.
So, Marr surrender their long unbeaten home record. “We re-group and move on.” said coach Craig Redpath.
Ayr coach Calum Forrester said it was “a proper derby, in front of a great crowd”, and praised his stand-in youngsters. “We had two teenagers at half-back and that we won shows the depth of our squad, but credit Marr for making us work for it.”