Assistant manager Ulrich Landvreugd was left to rue Barnet's poor start after the Bees lost 1-0 at Burton to an early penalty.
The Bees were unable to provide a tonic for sick boss Edgar Davids as Jacques Maghoma scored the only goal of the game from the penalty spot after just four minutes.
The visitors often produced the better brand of football on a tricky surface, only to be let down by a lack of cutting edge.
Landvreugd said: "Edgar has a virus and wasn't well enough to travel.
"I spoke to him on the telephone the whole 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 good, except for the first five minutes.
"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.
"I don't think you can ever overplay, but sometimes you can play a little bit more direct into the box."