Royals goalkeeper Lee Evans can only watch as Jon Froggatt's late free kick arrows into the net. (Picture: Tim Harrison)
Belper manager Peter Duffield made three changes to the starting line from the side that won at Carlton in midweek, with Shaun Roulston returning in place of Dan White, and Simon Harrison for Eric Graves.
Daryll Thomas was given a rare start ahead of Shaun Tuton who was named as a substitute.
Sutton Coldfield arrived at Christchurch Meadow 6 points adrift of the Nailers but nevertheless had a strong hold on a play-off place.
The game proved to be an uninspiring one until the last ten minutes as these two sides cancelled each other out for much of the 90 minutes.
Kristian Ramsey-Dickson and Luke Edwards had shots on the Belper goal in the first ten minutes as the visitors started in a lively manner, but the first close effort on goal from Belper arrived in the 18th minute when the referee unusually awarded Belper a indirect free kick after Lee Evans picked up a pass back from a team mate.
After a great deal of effort by the referee to get the Sutton players far enough away from the spot where the free kick was awarded, Jon Froggatt hit the cross bar with his effort.
Both teams expended a great deal of energy over the park for the rest of the first half without creating a notable opportunity and the 0-0 score line at the break was absolutely fair.
A sizeable bank holiday crowd looked for something extra as the teams kicked off the second half, but the game continued in the same vein as previously.
Sutton gave the Nailers an anxious moment in the 57th minute when Craig Lycett hit a bouncing shot just beyond the far post with Aaron Chapman diving at full stretch to ensure the ball went safe, and then Belper skipper Steve Warne headed a corner kick onto his own cross bar as the visitor’s enjoyed a good spell.
Simon Harrison nearly capitalised on some good work from Steve Warne and he struck a good shot from 15 yards that was deflected on to the underside of the bar.
Now there were signs, particularly after Mark Ward’s introduction in the 62nd minute, that the Nailers were beginning to ask some searching questions of the Sutton Coldfield defence.
The game seemed to be heading for a draw which may well have been an acceptable outcome for both sides, however the it exploded in the 87th minute when Jon Froggatt was held back as he looked set to run through on goal.
By the time the referee had sorted everything out Jon Froggatt stepped up with the game in the final minute of normal time and made the best of the opportunity by striking the ball into the bottom corner to give the Nailers a priceless lead.
Within seconds the game had its most contentious issue when Colin Marrison and Scott Lycett challenged each other for the ball as it ran out of play, and when the two players stood up, Lycett was seen to aim a head butt at Marrison, although it was the Belper player who was shown a red with Sutton player seemingly going unpunished.
The referee played an additional 8 minutes of added on time that only served to heighten the tensions that had only appeared in the final stages of the game, but Belper held on comfortably to their slender lead to take all the points.
Belper Town: Chapman, Wright, Rushbury, Cotton, Roulston, Adams, Harrison (Graves 69), Warne, Froggatt (White 90), Thomas (Ward 62), Marrison.
Sutton Coldfield Town: Evans, Lycett, Milligan, Parsons, Booth, Male, Cresswell (Leek 66), Sheldon (McNaught 76), Ramsey-Dickson (Danks 72), Edwards, Chapman.
Referee: Simon Brown (Redditch)
Att: 240
Match Sponsor: Molson Coors Brewers
Man of the Match: Andy Rushbury