Sandal sustained defeat for the first time since October 2012 when they were edged out 15-14 at Stockport.
The Milnthorpe Green men went into the National 3 North game having avoided defeat in every outing since the loss at Chester on October 13.
And they appeared to be on the road to another success when tries from James Briscoe and Simon Frewin, both improved by Greg Wood, put them 14-3 up at the interval.
However, the hosts hit back and Craig Anthony’s brace gave them a 15-14 advantage going into the final minute.
Sandal had the chance to win it with the last kick of the game but missed a penalty.