Chelsea manager Jose Mourinho says his players and the match officials should have all done better on Wednesday night against Maribor.
The Blues continue to lead Group G in the Champions League but the Portuguese believes his players should have been more aware of Maribor's strength.
"Many times surprises happen when people are not fully focused, when they believe the game can't be a difficult one," said Mourinho.
"Only when Maribor scored did the players realise the danger.
"If I cannot convince the players that the game is difficult and you have to play from minute one, obviously it's my responsibility.
"We scored two goals, two very good goals. The second goal, the referee decided to disallow but it's a clear goal.
"Normally we should win because we scored two goals. But we have to accept it.
"The referee's team did not have a good night."
