Belper Town dropped to seventh after a 3-1 home defeat to high-flying Brighouse Town.
Belper played well but Brighouse, who went second in the Evo-Stik League East Division, were the better side.
Both sides started well and after 15 minutes Brighouse left-back Sam Wright shot into the side netting from a tight angle.
Two minutes later Belper debutant Anthony Mackie’s left-footed finish, from a Nathan Curtis pull-back, was ruled out for offside.
The visitors took the lead in the 20th minute when Aaron Martin finished coolly into the bottom right corner, after a lay-off from Gabriel Johnson.
The hosts weren’t behind for long though, as less than five minutes later Piteu Crouz’s low cross hit Brighouse defender Kurt Harris, who was unable to do anything about the ball deflecting off him into his own net.
Belper might have gone in front in the 28th minute when George Milner played Mackie in, but the new man shot straight at keeper Matt Smith.
Smith made another fine stop ten minutes later, this time saving a powerful, stinging shot from Crouz.
At the other end, Martin nearly grabbed his second just before half-time, but his flicked header landed on top of the bar before bouncing over.
The chances continued after the restart, with Derry Robson nearly giving the Nailers the lead with an acrobatic effort.
In the 54th minute, Zephaniah Thomas saw his shot blocked on the line as Brighouse began to pile on the pressure.
A minute later, Belper keeper Leigh Overton, player of the month for December, tipped a superb volley from Martin over the bar.
However, from the subsequent corner Adam Field, the Brighouse captain, headed home.
Overton denied Martin again in the 61st minute, after the striker had been played in and was through on goal.
Eight minutes later, however, Martin finally did get his second goal of the match, pouncing on an error from Overton and rollinged his shot into the net.
After 74 minutes, captain Alex Peterson missed a golden chance from point-blank range to get Belper back into the contest, heading wide the post from a Craig Nelthorpe cross.
With a little over ten minutes remaining, Martin nearly had the chance to complete his hat-trick, but Nailers substitute Jake Sturgess tackled well to prevent the striker from getting a shot away.
In the 87th minute Belper had another opportunity to stage a late rally when Isaac Assenso couldn’t get enough direction on his header.