Crawley Town striker Tyrone Barnett scored the game's only goal in the third minute as the league leaders downed struggling Barnet.
The 26-year-old scored from the edge of the area when Kyle McFadzean miskicked Scott Neilson's corner.
Defender Dean Howell hit the crossbar three minutes later with a 30-yard drive as Town threated to run riot.
Crawley deserved their win, although Scott Shearer had to pull off a late save to deny Barnet's Izale McLeod.
The Red Devils remain three points clear of Cheltenham at the top, following the
The Bees are three points above the relegation zone, having played one more game than the bottom two.