The Gunners managed a 2-1 win in the first leg on the Champions League last-16 tie with Barcelona.
He said in The Sun: "We know we can beat Barcelona. We did that at the Emirates. Beat them again and we know we have a good chance of winning the tournament.
"We will go there with confidence but realise we have to defend well and hit them on the counter-attack.
"If we get a goal, they will have to come at us. We can win there.
"We do not want to go to Barcelona looking for a draw. It will be an open game and we will create chances. We are looking to score and then see what happens.
"We have shown we have the character to come back from a goal down against the best team in the world and are going there with a massive amount of confidence."