With a number of first team regulars missing, particularly midfielders Paul Coyne and Adam Logie, manager Steve Bateman drafted in Aylesbury United midfielder Paul Edgeworth, dual registered with the Rebels before the transfer deadline, to play his first game for Slough since the playoff final defeat at Chesham in May 2010. Bateman also named youth team players Gary Andrews and Joe Blount on the bench.
Rebels had started the game well, and had the first scoring opportunity when Stuart Swift's free kick found Sean Sonner at the back post. He played the ball across, but Leighton cleared their lines before Dan Burnell could get a telling touch.
Leighton went on to enjoy the better of the first half, but failed to turn their chances into goals and Paul Edgeworth's shot high and wide from distance was really the best Slough had to offer.
Three second half goals decided the game, the first of which came in the 53rd minute. Ross Hanley found space on the left hand side of the box, and placed his shot across James Warrington and into the far corner.
Slough's best chance to equalise was missed by Alex Brown, who blazed over after being found by Sonner.
With 71 minutes played, the visitors doubled their lead as Lewis McBride's free kick was flicked on by Leon Simpson for Ben Gallant to volley home, the Reds targetman completely unmarked.
By this point, Slough were well aware that St Neots had a commanding lead and were on their way to the title, and could only muster their first shot on target with ten minutes remaining.
Two minutes from the end, their misery was almost complete when Simpson added a third goal, converting Gallant's cross at the back post.
Worse was to come after the final whistle as Steve Sinclair was shown the red card for the second time this season after appearing to head-butt a Leighton player.
Leighton Town Line up
Hayden Dodge, Sam Chapman, Jake Bewley, Charlie Cunningham, Stuart Deaton, Sean Bishop, Ben Gallant, Enzo Silvestri, Leon Simpson, Ross Hanley, Lewis McBride. Subs: Alex Bradley, Jamie Bather, Nick May, Bradley Kirkwood.