Mikel Arteta says his Arsenal side need to stop being their own worst enemy after defensive lapses undermined their last-16 first-leg victory over Olympiakos in the Europa League.
While Martin Odegaard's opener paved the way for their win, familiar failings at the back saw the Greek champions level and made life uncomfortable until late goals from Gabriel and Mohamed Elneny swung the contest back in Arsenal's favour.
"We have to be very clear and honest with ourselves. We gave three chances to the opponent, they took one and at that level they are going to punish you," Arteta said.