Neil Baker and Jon Underwood called upon some old friends to represent the Rebels for this tie, with many first team players not being risked - former players Tom Biss, Tom Williams, Darren Wheeler and Dan Read all stepping in for one night. Williams had not played a competitive game in 18 months, Biss eleven months whilst Read took a place on the bench having played no football in almost two and a half years due to injury.
Jack Turner made a super save from a header on the half hour mark, but could not prevent Hayes taking the lead on 36 minutes with Manny Duku advancing into the box before blasting the ball past him.
Slough had created half chances of their own, but fell two goals behind on 48 minutes with a cross-cum-shot from right-back Keano Robinson flashing past Turner and into the top corner.
The hosts were then reduced to ten men on 55 minutes, Matt Hall seeing red for a second booking.
Read was introduced on the hour mark and late on, Biss fired over the bar, and then Nathan Webb had an effort saved by Xavi Comas before Read's follow-up was also kept out by the former Kings Langley keeper.
Slough pulled a goal back on 89 minutes as Lee Togwell sidefooted home from close range, but Hayes made sure of the win in stoppage time with Luke Joyce-Dwarika running clear and finishing well.
There was still time for Biss to have a goal ruled out for offside and then hit the post, but there was to be no comeback.
Hayes & Yeading United Line up
Xavi Comas, Keano Robinson, Darnell Shakes, Priestly Farquharson, Matt Hall, Komal Llewellyn-Reid, Scott Donnelly (Frankie Jones), Ola Olajubu, Manny Duku, Ismael Ehui (c) (Toby Little), Luke Joyce-Dwarika. Unused substitutes: Luke Daley, Joakim Ehui, Stephen Ellery.