Barnet were consigned to a fourth game without a win after a 3-1 loss away to Alfreton Town.
John McGrath opened the scoring for Alfreton with a free-kick. Keanu Marsh-Brown equalised for Barnet at the start of the second-half, but a Paul Clayton double saw the hosts retain their imperious unbeaten home record.
Barnet remained unchanged from the side that salvaged a point away to Aldershot Town on Tuesday, with Harry Crawford retaining his place upfront amidst competition from fellow striker Marciano Mengerink.
Alfreton Town took the lead after 13 minutes. McGrath perfectly executed his free-kick, curling the ball into the top corner of Graham Stack's goal from 25 yards.
Alfreton continued to threaten Barnet, who, again, were sloppy defensively. John Akinde should have done better with a lob after a ball was headed over the defence, while Clayton missed a guilt-edge chance, with his free-header just outside the six-yard box hitting the top of the bar.
Barnet failed to create any meaningful opportunities, with the midfield constantly passing backwards - tantamount to watching a rugby team. Marsh-Brown had their best chance, hitting the side netting at the end of the first-half.
The influential winger proved yet again to be a source of inspiration, notching an equaliser three minutes after the restart, taking on a fine Curtis Weston pass before firing from just outside the box past Ross Atkins.
The Bees' revival did not last long. Akinde's jinking run and cross caused a series of problems for the Barnet defence, with Clayton forcing the ball home.
On 58 minutes, Clayton scored his second goal of the day and gave his side a two-goal cushion. After Stack parried a shot away, the ball was not cleared, allowing a cross to be fired in to Clayton to score a carbon copy of his first goal.
Two minutes later Alfreton could - and should - have made it 4-1. Akinde, who was free of the defence when through on goal, miscued his shot wide of the post.
Marsh-Brown's replacement, Portuguese winger Mauro Vilhete, was Barnet's most attacking and inventive outlet and he had their best chance of the second-half, firing a long-range effort wide of the mark.
The result saw Barnet slip out of the play-off zone to 8th place, falling eight points behind table-toppers Cambridge United.
Meanwhile, Bees midfielder Freddie Warren has joined Isthmian Premier Division side Canvey Island on a one-month loan.
Barnet: Stack; Yiadom, Acheampong (Mengerink), Stephens, Johnson; Byrne, Weston, Abdulla; Marsh-Brown (Vilhete), Gambin (Luisma), Crawford.