SELBY RUFC lost their place in the top four in Yorkshire One as they lost 18-11 at Bridlington.
The Swans were overtaken by Old Brodleians in the table after their top-four rivals trounced Acklam 77-13 on Saturday.
Fly-half Josh Cruise kicked the visitors into a first-minute lead on the east coast with a penalty, but the home side levelled three minutes later through Lee Terewi.
Terewi missed with a second attempt on 11 minutes, but Brid forged ahead on 14 minutes with an unconverted try by Garry Stevens.
It was 13-3 on 18 minutes after Ryan Stirk crossed, although Terewi was off target with the boot again.
A second Cruise penalty on the stroke of half-time meant Selby turned around 13-6 down.
A 27 minute period of second half stalemate was broken when Garry Heeley went over for a third Brid try, which was also unconverted.
In the second minute of stoppage time, the Swans finally crossed the line, with captain Duncan Hardy touching down.
With two games of the season remaining, Selby are level on points with Old Brods, although with a vastly inferior points difference.
York are only seven points behind their North Yorkshire rivals in seventh place after a 38-35 triumph at home to Pontefract.