In awful conditions, Ayr got off to a bright start. Frazier Climo scored a converted try in the seventh minute after great work from Scott Lyle and Grant Anderson. The lead was 14-0 soon after when Jonathan Agnew went over for a second.
Michael Allen’s converted try gave Watsonians points on the board at 14-7 before he and Craig Borthwick were yellow carded. Lyle and Ali Harris then traded penalties to make it 17-10 to Ayr at half-time.
A converted Sean Crombie try levelled things before a converted try from Steve Longwell and a Lyle penalty were added for Ayr.