George Wells slotted home the decisive spot-kick to send the Rebels into delirium, after the match had finished 1-1 after 120 minutes of play.
National League side Sutton made a strong start and took a deserved lead when Harry Beautyman diverted Josh Taylor’s angled drive past Jack Turner from close range with just nine minutes played.
Slough held out and weathered the storm, emerging as the better side in the second half and deservedly levelling the scores through James Dobson's powerful free-kick on 81 minutes.
The Rebels had the better of the game in extra time without being able to find a winning goal, and almost inevitably the game was decided by a penalty shootout. Slough ultimately emerged victorious but not without drama, as Sam Togwell put his effort wide of the post when he had the chance to win it after Jack Turner had saved from Tom Bolarinwa. Luckily for Slough, Dean Beckwith skied his penalty moments later, leaving Wells with another chance to secure the win – and his kick, whilst not convincing, found the back of the net.
The shootout concluded what had been 210 minutes of action, with two hard-fought and very close matches. Like in the first match, the conditions were far from ideal with rain throughout but the 3G surface meant both teams could still play good football.
Sutton quickly showed their class when Taylor burst down the left and got into the box, where his shot was touched in by Beautyman for the opener.
Sutton gained huge confidence from the early goal and pinned Slough back. Another driving run from Taylor put the Rebels on the back foot and his dangerous cross was only half cleared with Beautyman seeing his effort deflected wide.
On the quarter hour mark the visitors had their third chance as the imposing centre-half-turned-striker Charlie Clough controlled a long ball forward on his chest before quickly hitting a half volley which Turner could only watch bounce back off his crossbar.
Sutton were well on top and would go on to rue those missed opportunities to take a stronger lead.
It took over 20 minutes for Slough to create anything of note. A long cross field ball found Warren Harris in space, and his cross was a good one but Mathew Stevens couldn’t get enough power on his header to trouble Ross Worner in the Sutton goal.
Slough were now ever so slowly getting themselves back in the match and having sights of goal. In fact, they would have the next chance as a low cross from Josh Jackman found Stevens in the box but his shot was well blocked and the ball went over the bar.
Sutton will rue not taking one of their chances after the interval. Clough continued to make a nuisance of himself, forcing a corner from which Taylor had a good chance, but his shot was blocked by one of the many Slough defenders.
Wayne Brown's well-placed finish was kept out by Turner’s fingertips, whilst Jonah Ayunga blasted wastefully wide with only Turner to beat after being released by Craig Eastmond in a swift break in the 58th minute.
Beautyman also curled a free-kick inches wide and Jamie Collins saw a header from a corner fly across goal and wide of the far post.
This miss seemed to really spur on the Rebels and with the introduction of Ben Harris and Simon Dunn, presented Sutton with new problems.
Dobson forced Worner into a good save from a free kick from 25 yards, but shortly after would have more joy with another right on the edge of the box. Referee Brett Huxtable penalised Sutton for a handball offence in a central position and up stepped Dobson to unleash a rocket through a gap in the defensive wall which Worner had no hope of seeing, let alone saving.
Slough were deservedly level and pushed for a winner, and the closest they came was from Dunn, who fired just over after being found by Manny Williams.
There were few chances for either team in extra time, but again the best of them fell to Slough with Dobson dragging two efforts wide of the target.
After ten perfect penalties, Turner saved from Bolarinwa and Sam Togwell missed, but Beckwith skied his attempt, leaving Wells to grab the glory and seal Slough’s progress.
Slough Town Lineup
- 1 Jack Turner
- 2 Josh Jackman
- 3 George Wells
- 4 Sam Togwell
- 5 Mark Nisbet
- 6 Lee Togwell
- 7 James Dobson
- 8 Scott Davies 15
- 9 Chris Flood 18
- 10 Mathew Stevens
- 11 Warren Harris 19
Sutton United Lineup
Ross Worner, Dale Bennett, Aswad Thomas, Dean Beckwith, Charlie Clough, Jamie Collins (c), Josh Taylor (Tom Bolarinwa 88), Wayne Brown (Kenny Davis 90) (Kieron Cadogan 111), Harry Beautyman, Jonah Ayunga (Aaron Drinan 64), Craig Eastmond. Unused substitutes: Dan Wishart, Seb Brown.