A late header from Harry Ransom was enough to win the match as we were beaten 1-0 by Dover Athletic on the opening day of the 2020-21 Vanarama National League season.
The defender crashed a header off the underside of the bar in the final minute of normal time to earn his side the three points on an afternoon where several opportunities passed us by.
Cal Roberts was fit enough to start the match despite having been stretchered off the field against Harrogate Town on 22 September.
Roberts was handed a right-wing berth with Jim O'Brien on the opposite flank and Michael Doyle partnering Jake Reeves in central midfield.
Behind them, Alex Lacey and Connell Rawlinson were selected to marshall the centre of defence with full backs Richard Brindley and Adam Chicksen completing Slocombe's line of defence.
Up front, Wes Thomas paired up with Kyle Wootton, while Sam Graham, Dion Kelly-Evans, Enzio Boldewijn, Ruben Rodrigues and Jimmy Knowles had to settle for a place on the bench.
Dover announced no fewer than four new signings ahead of kick-off and one of them, centre forward Ade Azeez, nearly prised open the door with an excellent cross from the right which was well dealt with by Brindley inside three minutes.
Our response came when Reeves played a nice through ball for Wootton, who was unable to apply the finishing touch to his mazy run inside the area.
The hosts were forced into a change on 10 minutes when Josh Passley was forced off in place of Travis Gregory, and the new arrival nearly saw his side go a goal behind almost immediately as O'Brien sent a low shot just wide of the post.
Roberts fired an effort straight at the opposition keeper shortly before Brindley saw his strike deflected wide as we continued our pursuit of the opening goal.
And Roberts' influence continued right up to half-time as he first nodded the ball down for Reeves, who saw his shot blocked, before the Geordie was crowded out by a defender at the near post after being well picked out by Doyle.
We emerged for the second half unchanged and could well have fallen behind within three minutes of the restart when Jack Munns picked out Steven Rigg with a pinpoint cross. The big forward couldn't find a way past Slocombe from point-blank range.
The hosts had begun the second half the better and drew a booking from Reeves when Will De Havilland brought the ball out of defence before being felled by the midfielder in shooting range. The resultant free-kick didn't go according to plan and the danger was over.
We began to find our feet again shortly before the hour, however, and after Thomas and Reeves had both seen shots blocked in quick succession Roberts bent an effort just beyond the top corner from the edge of the area.
Moments later, Reeves' driving run from midfield took him into the Dover penalty area but he could only drag his effort wide of the near post.
And we kept up our pressure through Roberts, who showed good feet in the box to buy space to shoot only to see his low, well-struck effort saved.
Wootton was next to try his luck when he latched on to a corner but failed to wrap his foot around the ball, sending his effort over the bar.
Second-half Dover substitute Bilel Hinchiri's overhead kick went over and Jimmy Knowles and Enzio Boldewijn replaced Thomas and O'Brien as full-time approached.
In the dying moments Roberts had a golden opportunity to win the game when he carried the ball across the edge of the area before sending his shot straight at the keeper.
And our frustrations were exacerbated when, in the 90th minute, Ransom rose highest from a corner to head home the winner.