These two clubs will once again likely be competing for the title this season and, on this evidence, it will be difficult for their league rivals to keep up.
George Graham Sr, the Gala head coach, was disappointed at the result but was not too disheartened by the performance from his side. "Ayr took their chances, we didn't, but we created several and played some great rugby, particularly in the second half," he said.
"We kept the ball well in the first half but our discipline let us down. Still, considering we haven't recruited and were without our two club international props from last season, as well as one or two injured guys who might have started, I am reasonably happy to emerge from a difficult place with two bonus points."
Callum Forrester, the Ayr head coach, was taking charge of his first competitive match and savoured the victory. "This is a lot harder than playing," he said.
"We made a hesitant start but retained possession well and deserved to lead at the break. We knew they'd hit us hard after the break but we held them well and I feel we should have killed them off earlier, it was a good win."
Forrester praised scrum-half David Armstrong, who was making his competitive first-team debut. Both he and Ayr stand-off Danny McCluskey were the second XV halves last season, behind Murray McConnell and Finn Russell, now of Glasgow Warriors. The two youngsters stepped-up well, with Armstrong snatching a try.
Blair McPherson, back at his first club following two years with Hillhead-Jordanhill, also scored from No.8. However, Ayr's slender propping resources were underlined once Fraser Watt went off, allowing Gala to take control in that department.
After Graham's first-minute try, converted by Craig Dods, Ayr surged in front as Ross Curle scored with two penalties and a conversion - while also missing the conversion from McPherson's try - for a 18-7 lead at the break.
Grant Somerville reduced the deficit, before Grant Anderson scored for Ayr and Curle converted to put Ayr 25-12 up after an hour. A Gala penalty try was converted by Dods, then Curle replied with a penalty, before a late, unconverted try from Josh Irvine made for a tense finale. Ayr stood firm, however.
There were two episodes of handbags - appropriate for Ladies Day at Millbrae - with Gala's Chris Weir seeing yellow for the first, while Ayr's Craig Gossman was hospitalised after dislocating his left elbow in the second half.