Laurent Koscielny: Arsenal must get out of 'negative spiral' after defeats

Europa League Predictor: Round of 16 (2:51)

Alexis Nunes and Shaka Hislop predict the biggest ties in the last 16 of the Europa League, including the big clash between Arsenal and Milan. (2:51)

Arsenal centre-back Laurent Koscielny warned that his teammates must get out of their "negative spiral" and need to push through their recent struggles to achieve success in the Europa League.

The club enter the round-of-16 tie away against AC Milan on Thursday having lost four consecutive games, including the second leg of their Europa League round-of-32 tie against Ostersunds at the Emirates Stadium last month, for the first time since 2002.

"To be together is the most important," Koscielny said at a news conference on Wednesday. "It doesn't matter what is going on outside. We need to stay together as a team.

"We are in a negative spiral and it's difficult to get out of this, so we need to stay positive in our heads because the brain dictates our legs and our body. We have the quality to push ourselves and to have a great result to give us more confidence and then, step by step, to come back stronger."

In addition to the defeat against Ostersunds, Arsenal lost twice to Manchester City -- once in the Carabao Cup final -- and also against Brighton & Hove Albion on Sunday.

Milan enter Thursday's game on a 13-game unbeaten run and they have not conceded a goal in their last six matches.

Koscielny is one of the few players who have remained with Arsenal since their 4-0 loss at Milan in the first leg of the round-of-16 Champions League tie in 2012.

"In this competition, it's always important because we play two games, the first one is always very important to negotiate well," Koscielny said. "When we came here last time, we didn't."