Manager Robbie Neilson denounced Scott Wootton and George Williams after Dons 2-0 defeat at Peterborough on Tuesday night.
The Scot felt the two playing at the heart of Dons' defence were to blame for the loss at the Abax Stadium, allowing the Posh front line to bully them.
Despite matching the home side for the first 45 minutes, seven minutes of lacklustre football in the second allowed Ryan Tafazolli to head Posh into the lead before Marcus Maddison bent in the second shortly afterwards.
Speaking afterwards, Neilson said Williams and Wootton needed to be stronger and held the pair responsible.
"The key thing for us, was not fighting enough at centre back and in those sorts of areas," he said. "Williams and Wootton are good, strong players and they'll bounce back from that.
"Ultimately, we had to deal better from set plays. The centre halves had to do better, the goalkeeper had to do better. We had to be stronger. Even in the first half, we weren't getting clean contact and they were getting opportunities. We have to do better in these situations because it's as simply as bread and butter. It has to improve.
"Maddison has very good delivery, but you expect your stronger and more physical players to man up to it and win the headers. We didn't do that.
"I thought a few of them were really good tonight, but you have to do the basics in football. If you can't do that and let two strikers dominate us, you're not going to win games.
"This will be a wake-up call for them. First and foremost, you have to win the individual battle, then you can go forwards and let our players go up and play. Things like this are unacceptable - we can't be losing goals from set plays.
"That's part of football and he needed to be stronger. Tonight, we weren't strong enough in the central defensive and goalkeeping areas. Those three have been great for us all season and they had a blip tonight. We cannot afford to get bullied in those areas."
While Neilson pointed the finger at his defence, Aaron Tshibola was guilty of giving the ball away for the second goal, and all too often looked disinterested in being on the field.
Neilson however, defended the on-loan Aston Villa midfielder, saying: "It's a silly mistake but i'm not too bothered by it. He's trying to take a chance on it and make a break - you've got to ask players like that to take a chance.
"We got into good areas with Tshibola and Gilbey, who I thought was excellent tonight, but it was down to not being aggressive enough."