The Middlesex hosts, on a seven match unbeaten run going into the game, perhaps edged the opening half an hour as the game developed into a midfield battle on a fine Spring afternoon.
Joe Chandiram fired wide before Ed Smith produced a good save from Lee Pearce, with the Greenford defence able to hack the ball away.
Jake Parsons fired wide from 25 yards after a corner was half-cleared, but in the 35th minute, Greenford striker Awoala Kpunpamo met a fine cross from the left to head past young Rebels goalkeeper James Hawtree from close range.
But six minutes later, Slough hit back after a good spell of pressure. A corner won on the right by Jake Parsons was swung in by Danny Murphy, and Alex Brown rose highest amongst defenders and goalkeeper Lee Pearce to head in.
Greenford had a chance to go back in front early in the second half, with Kpunpamo again involved, but he shot wide.
On 57 minutes, Slough took the lead with a goal in fortuitous circumstances. The Rebels cranked up the pressure with Ashley Deeney winning a corner after a surging run down the right, and Greenford again showed their fragility in defending set-pieces as Lee Pearce punched the ball into his own goal under pressure from Dave Woozley as he came to meet Murphy’s ball in.
The game opened up and Slough went in search of a third, but Pearce did well to deny Chandiram after Ryan O’Toole had found him in the middle of the goal.
Pearce also did superbly to spread himself and block two efforts, first from Parsons and later substitute Ollie Burgess, who tried to blast a shot past Pearce from a narrow angle, but the goalkeeper kept it out.
Unfortunately for Pearce, his game ended early as he was dismissed with around seven minutes remaining, conceding a penalty which would wrap up the three points for Slough. After Burgess had won the ball back and had a shot well saved, Smith picked up the rebound and had just Pearce to beat. The keeper did well to block his initial effort, but he then dragged the striker to the ground as he was about to score, leaving Slovakian FIFA referee Alexandra Ihringová with little choice but to send him off.
Veteran forward Mark Nicholls donned the gloves and number one jersey, but was sent the wrong way by Smith, who notched his 29th goal of the season to become Slough’s top scorer this season.
Slough saw out the remainder of the game with relative comfort, without testing Nicholls again and ensuring Greenford could not find a path to goal to mount a comeback. Slough now travel to Thatcham Town on Tuesday for their penultimate league match, followed by a home match against Chertsey Town next Saturday to complete the league campaign.
North Greenford Utd Line up
Lee Pearce (c), Sean Hillier, Dan Carter, Wayne Jackson (Anton Robinson), John Sonuga, Liam Hind, Edward Hatcher, Mark Nicholls, Zak Joseph (Chris Drake), Awoala Kpunpamo (Daniel Vincent), Aaron Silcott. Subs not used: none