Djourou was disappointed with the ‘silly mistakes’ that his side made in the game.
The Switzerland international told Sky Sports: “It’s crazy.
“We had the game under control and two counter-attacks and silly, silly mistakes – we can be disappointed because we should have won the game easily, it’s very hard to take.
“A point would have qualified us so it’s a shame to concede goals like that, I just cannot understand. We have to look again, that shouldn’t happen. It was a lack of concentration, the team needs to concentrate and do better than that.
“The team needs to know that now we have to wake up, it was a big wake-up call.
“We have a big game against Partizan and we have to win that to qualify for the knockout stage.”
