Villarreal goalkeeper Diego Lopez insists they can still overcome Europa League semifinal opponents Porto.

Lopez refuses to give up on the possibility of reaching the Europa League final in Dublin, despite starting Thursday's second leg at home to Porto 5-1 down on aggregate.

"We need to believe in ourselves first so we can turn the tie around," he said.

"It could hardly be more difficult, but it's not impossible. It's going to be difficult but in the dressing room we are convinced that we can achieve it."