Arsenal boss Arsene Wenger has admitted that he is wary of the impact of Atletico Madrid forward Diego Costa ahead of Thursday's crucial meeting in the Europa League.
The Gunners take on Atletico at the Wanda Metropolitano needing to at least score a goal in order to maintain their chances of reaching the final of the competition.
Former Chelsea forward Costa is expected to feature for Atletico, and Wenger admits that the Spain international has the potential to make the difference in the tie.
At a press conference, the Frenchman told reporters: "In history he has shown he can make differences. It's our job to keep him quiet, maybe the best way is to play in our half and not in the half of Atletico Madrid."
Costa has scored six goals in 19 appearances for Atletico since leaving Stamford Bridge in January.