It was a full 16 minutes before either side had a sight of goal, the first attempt arriving when, following a well rehearsed free-kick on the edge of the penalty area, Saints' top scorer Peter McDonald sent his shot wide of David Barthelot's left-hand post.
Five minutes later, however, Raith took a surprise lead with their first serious attack of the game. A corner from Scott Crabbe on the left caused havoc in the St Johnstone goalmouth and, as the visiting defenders failed to deal with the danger, young Pat Clarke, on loan from Dunfermline, drove the ball home from close range.
Rovers' lead lasted a mere 10 minutes, Saints equalising with a similarly scrappy effort. Ian Maxwell sent a long throw-in from the left into the danger area and, as the hesitant Raith defence failed to clear, Steven Anderson forced the ball over the line.
Rovers indulged in some spirited attacking in the second half as they sought the victory which would have given them a stay of execution, but it was Saints who took the points when substitute Kieran McAnespie fired home the winner in the 78th minute with his first touch of the ball.