The Gunners will head into the second leg of their last-16 tie against Bayern Munich on Wednesday 3-1 down from the first leg played at the Emirates Stadium in London last month.
"We come into this game to win and get through," the defender told reporters. "Last season against Milan, we almost did it when most people thought it was impossible. A lot of players know that and they all believe we can win.
"In football, anything can happen. Of course it will be difficult, but we believe in it. Football is a strange sport, so we will go for it."