Craigroyston created the first chance of the afternoon when Dean Horribine pounced on a slip by Kyle Sneddon only for Kyle Moran to make a wonderful save to deny the young striker.
St Andrews United’s first opportunity came four minutes later when Jack Wilson lobbed the ball over the bar from a good Sneddon pass.
The opening goal of the game came when Jake Grady burst down the left wing before sending a low cross into the box which Wilson flicked into the path of Matthew Irvine.
The trialist student hooked the ball into the net with his left foot from close-range in the 19th minute and the goal gave the home players a massive lift.
The second half began badly for Saints as Craigroyston stormed down the slope to equalise in the 48th minute.
Gary Nicholson beat the offside trap when he raced towards Moran. The young goalie actually did well to force his opponent wide of the target, which made shooting difficult, yet Nicholson managed to cross for Renton to slide the ball into an empty net.
Alas, that goal knocked the stuffing out of Saints for a while and worse was to follow because Jason Penman limped off the park with a nasty looking ankle injury.
The lively Renton rounded Moran to give his side the lead for the first time in the 75th minute.
It was an advantage they would hold in to despite late chances for Saints through Michael Fleming and Kai Pannwitz to equalise.
Things took a sour turn for Saints in midweek when they found themselves on the wrong end of a 7-0 scoreline against Dunipace.