Barnet have seen their lead at the top of the Conference Premier table cut to one point after they suffered a last-minute defeat at home to Grimsby Town.
Before Christmas, the Bees' lead had been stretched into double figures but two late goals from Craig Disley and John-Paul Pittman have condemned the Londoners to a 3-1 loss.
Bristol Rovers have taken full advantage of the slip-up from their rivals by recording a 1-0 victory over Altrincham.
Forest Green Rovers remain in the title picture after three goals in the final 25 minutes earned them a 3-0 triumph over bottom-placed AFC Telford United.
Eastleigh remain five points off a playoff spot after a Dan Walker goal secures a 1-0 success away at Chester FC, as do Halifax Town who had Jamie Jackson to thank for a last-minute strike against Braintree Town.
However, Kidderminster Harriers lost ground after being held to a 0-0 draw against Nuneaton Town, who remain six points adrift of safety.
Alfreton Town failed to move out of the relegation zone after conceding three goals either side of half time to fall to a 3-2 defeat at home to Aldershot Town.
The other match of the afternoon saw Southport twice come from behind to record a 2-2 draw away at Dover Athletic.
Results in full: Alfreton Town 2-3 Aldershot Town, Barnet 1-3 Grimsby Town, Bristol Rovers 1-0 Altrincham, Chester FC 0-1 Eastleigh, Dover Athletic 2-2 Southport, Forest Green Rovers 3-0 AFC Telford United, Halifax Town 1-0 Braintree Town, Nuneaton Town 0-0 Kidderminster Harriers