Liam Hatch was Barnet's goal hero as the Bees secured a crucial win over Mansfield in their relegation battle.
The striker netted his first goal since last April as the Bees moved three points clear of the relegation zone.
The victory should have been made easier as Mansfield had two players sent off in the second half, but the home side still had to survive some tense moments at the end.
Hatch also had a goal ruled out for hand-ball but it didn't matter as Barnet got a deserved victory.
His goal that did count came after 10 minutes – a lightening strike from 10 yards after Mansfield failed to clear Nicky Bailey's corner. It was the striker's first goal in league football and it could not have come at a more opportune moment.
Barnet's best hope of doubling their advantage came from Hatch, who had a hat-trick of headed opportunities around the half hour mark.
He appeared to have got that vital second goal on the stroke of half-time when he tapped home after beating former Sheffield Wednesday keeper Kevin Pressman in the air, but he was adjudged to have used a hand in the challenge and got a booking for his troubles, much to the disgust of the Underhill faithful.
After the break, Barnet's hopes of securing the points were made easier when Mansfield were reduced to 10 men after Giles Coke went for his second booking after getting into a scrap with Barnet's Barry Fuller. Then substitute Danny Reet was shown a straight red for a late tackle on Bailey after 70 minutes.
Even with a two-man advantage Barnet had to hang on, and with a minute to go Mansfield top-scorer Richie Barker missed a glorious chance to level but put his header wide from six yards.