Barnet assistant head coach Ulrich Landvreugd admitted Barnet paid the penalty for their poor start in the 1-0 defeat against Burton Albion.
The Bees, who were without Edgar Davids due to illness, went behind after just three minutes as Jacques Maghoma was fouled in the box by Barry Fuller. The winger dispatched the resulting penalty past Graham Stack.
The rest of the first half was controlled by Barnet but without the injured Jake Hyde, they lacked a real threat in attack.
The second period continued in the same fashion, although Burton did look dangerous on the counter attack.
The Bees were unable to find a way through an organised Brewers defence and they suffered their first defeat on the road since December 15.
Landvreugd was pleased with the overall performance but was disappointed with the Bees sluggish start.
He said: "Edgar has a virus and he was not well enough to travel.
"I have been speaking to him on the telephone throughout the day on how we were going to play, right up to five minutes before the game.
"I'm disappointed with the result because we played quite well, except for the first five minutes of the game.
"We knew how Burton would play, with the long ball to the striker and everyone working around him. We trained on that but that was what got them the goal.
"We had a few chances but generally the final ball into the box was disappointing after some good build-up play and we didn't give the goalkeeper a lot of pressure.”