Rion Benjamin-Potts struck in the dying moments as the Nailers won 2-1 at Loughborough Dynamo on Easter Monday, meaning his side has a two-point advantage over sixth-placed Carlton Town going into Saturday’s home game with Corby Town.
Should they equal or better Carlton’s result against Stamford, they will then have a play-off semi-final next Tuesday night away to the second-placed side.
Black said: “It was a dreadful game and the quick turnaround at this level to play Saturday and Monday is a killer and both teams were out on their feet from minute one.
"But we just said to the lads at half-time that the ones that could keep going mentally for 90 minutes and have the desire to get the points will win it.
"Credit to Loughborough who had nothing to play for but made it hard for us so our lads knew they had to be patient.
"Anyone who ever doubts this group of lads we’ve got has seen it in abundance today – they’ve gone 1-0 down with barely a team and we keep digging, get a goal and then want to get another one.
“Everyone in the town of Belper and at the club should be proud of what they’ve got.
"If we don’t get into the play-offs there will be nobody more devastated than me and the lads but what they’ve done this season with what we’ve got and what we’ve had happen in the last three or four weeks [with injuries] is unbelievable, so whatever happens next week, let it be.”