United defender, Martin Smyth netted a very impressive brace, scoring twice from outside the box.
The game got off to a blustery start with both sides struggling to control the ball against the elements. However, it was Belper that took control of the early stages, threatening the Wrens defence from the start.
Belper were unlucky not to take a lead in the 10th minute as Joshua Wright struck the bar. The forward weaved in well from the left before unleashing a looping ball onto the frame of the goal and away to safety.
The visitors thought they had taken the lead in the 25th minute as Marc Strzyzewski headed home Ben Robinson's corner delivery. However, the referee would rule the goal out for a foul to give the Wrens a lifeline, although the foul in question was not a clear one.
Three minutes later and Belper went close again. Efficient link up play between Williamson and Wright would see the visitors advance quickly down the right flank. The cross from Wright found Richard Hanslow unmarked in front of goal, however the striker could only drag his header wide of the target.
Belper United finally took their deserved lead in the 37th minute through midfielder James Ozmen. Hanslow had worked the ball into the box well before his shot was blocked, falling to the feet of Ozmen who shot on the turn finding a gap at the near post.
Three minutes before the break Belper should have doubled their lead. A long-range effort from Ozman landed excellently at the feet of Martin Smyth in front of goal, however the defender missed the ball completely. Joshua Wright’s follow up shot was then superbly saved by Warren Squires in the Rainworth goal.
The visitors restarted the second half remaining in control. Three minutes into the half, Curtis Williamson forced Squires into a save as he parried the forward’s curling effort wide of the post.
It wouldn't be long until Belper doubled their lead as Hanslow converted a one on one chance. Winger Joshua Wright sent Hanslow on his way with an accurate through ball before the number nine fired calmly past the keeper.
The visitors again came close to finding a goal, this time in the 70th minute. First, Joshua Wright squared to Hanslow who couldn't connect with the ball despite finding himself on the goal line beyond the Wrens keeper. Soon after, Curtis Williamson was sent straight through on goal but could only put his effort to the left of the goal.
Rainworth came close to getting one back in the 77th minute through Ryan Herbert. The midfielder found space outside the box to get a shot off that skimmed the outside of the right post.
Two minutes from time Belper found their third of the game through an excellent long-range strike from Martin Smyth.
In the 91st minute the visitors found their fourth again from Martin Smyth. Smyth drove effortlessly through the Wrens midfield before his shot from outside the box deflected off Jack Havron and into the left side of the goal.
The fourth goal ended a game in which Rainworth were completely out played by Belper United, however the Wrens will be hoping they can bounce back away to Teversal on Tuesday night.
Rainworth: Squires, Bamford, Weaver, Havron, Wright, Hempshall, Harris, Herbert, Brooks, Darby, Wootton
Subs: Fisher, Mason, Coupe, Smith, Jones
Belper United: Whittingham, Leigh, Guy, Smyth, Strzyzewski, Simpson, Robinson, Owen, Hanslow, Williamson, Wright
Subs: Rushby, Dodds, Jones, Garnett, Mulonga