Laurent Blanc admitted Paris Saint-Germain 'lacked something' during Wednesday's 3-1 defeat to Barcelona.
Les Parisiens squandered top spot in Champions League Group F following defeat at Camp Nou, and the Coach lamented his side's failure to carry out his pre-match instructions.
"We could have drawn, but we missed things like defensive efficiency," he complained to reporters after the game.
"Our opponents were not that dangerous but still scored three goals. We had shortcomings and lacked our usual standards.
"We had to take risks, we were 2-1 down and thought we needed to get some fresh attackers on to pose our opponents problems. We wanted to take risks, but in the end we didn't from the start of the match.
"We conceded a goal which could have been avoided, but at first we created danger for Barcelona. We believe our midfield worked, but for games like these, the system has to be excellent.
"We lacked something and could have defended better, that's all. I came here hoping to finish first. We failed, but the players have fought tooth and nail.
"We'll wait for the draw to assess the extent of finishing second. Many teams will suffer the same fate as us in Catalunya. It's difficult not to be defeated here."