The Rebels dropped off the pace, set by newcomers Royston and Godalming, after a prolonged run in this season's FA Cup.
But Steve Bateman's team closed the gap on top spot to nine points following a 3-1 win at Chertsey Town last weekend.
And Slough, runners-up last term, could move within striking distance of the play-offs with victory at AFC Hayes on Tuesday.
Danny Burnell opened the scoring rather fortuitously at Alwyns Lane, firing past Tony Oval from 20-yards after the Chertsey goalkeeper was caught out of position in anticipation of a back pass.
Chertsey hit back minutes later when Mark Knight headed a Rob Carr cross past Rebels stopper James Warrington.
Bateman's men were fortunate not to fall behind as the hosts twice struck the woodwork in a fractious encounter.
But they were gifted an opportunity to restore the advantage six minutes from time following a foul on Sean Fraser by Michael Blount.
Slough were incensed a red card was not shown to the Chertsey captain, but Burnell kept his cool to slot past Oval from the spot.
Metropolitan Police loanee Ed Smith made sure of the points with a smart 25-yard lob four minutes into injury time.
Burnham FC's brief stay at the top of Division One ended after a heavy 3-0 defeat against Biggleswade Town at The Gore.
The Blues became the third table-topping team to be humbled by Biggleswade, though Martin Stone's team remain firmly in the play-off positions.
The Waders broke the deadlock in the 16th minute when Andrew Iwediuno met Lee Allinson's cross at the far post.
Biggleswade's lead was doubled midway through the first half courtesy of a Brett Donnelly strike.
Michael Watkins kept Burnham in contention after the restart with several smart stops but was beaten for a third time by substitute Jamie Alick in the 66th minute.
Beaconsfield SYCOB were condemned to a third defeat in four matches after a 2-0 loss against Ashford Town (Middx).
Ed Thomas broke the deadlock at Holloways Park inside two minutes with a spectacular 30-yard volley.
Despite their dominance, The Rams failed to find a way back into the match and fell further behind when substitute Perry Luckins made it 2-0 five minutes from time.
The Rams could re-ignited their promotion push with a home win over Leighton Town tonight (Monday).
Elsewhere, Maidenhead United dropped into the relegation places in Blue Square Conference South following a 2-1 defeat against Eastbourne Borough.
The Magpies were left stunned by Eastbourne's late comeback and have now suffered defeat in eight of their last 10 league matches.
Harry Pritchard gave Johnson Hippolyte's team a 16th minute lead but Maidenhead were made to pay for missed chances.
Elliot Charles levelled for Borough on 77 minutes before substitute Darren Lok bagged a winner five minutes from time following a horrible error from United keeper Jessie Joronen.
Windsor FC recorded back-to-back wins in the Combined Counties Premier Division after a 1-0 victory at Molesey.
The Stag Meadow-based club put a recent defeat at title challenging Guernsey behind them with a thumping victory against Ash United.
And Micky Woodham's team maintained their mid-table status with a narrow victory at Walton Road.
Josh Parker provided the game's only goal, a 25-yard effort past Molesey keeper Wester Young.
Finally, Holyport succumbed to a sixth consecutive defeat in all competitions after a heavy 4-0 loss at Hellenic Premier Division leaders Marlow.
The hosts opened the scoring after half an hour's play when Michael Bartley headed home Marcus Mealing's curling free-kick.
Ian Davies doubled the lead minutes later when his through ball evaded everyone on its way into the Holyport net.
Derek Sweetman's team worked hard in the second half but conceded a third 10 minutes from time, Davies firing a Ben Gladwin pass beyond Ashley Smith.
Chris Ovenden completed the rout five minutes from time, firing home with the aid of the crossbar.
** PICK up a copy of the Observer, out Friday, for full match reports and all the latest news from your club. **
** FOLLOW the Observer on Twitter @Observer_sports **