The two teams clash in the last 16 of the competition as Barcelona continue the defence of their trophy.
Lopez knows his team face a very difficult task about Barcelona but says they do have a chance of going through.
“We’re facing the most in-form team, one of the best in the world for their style of play and everything else,” he told reporters. “When the ball starts rolling, it’s 50/50.”
“We have a very important match on Sunday—the team hosts Las Palmas—because our goal is promotion, but against Barça we’ll field a very strong starting eleven to put up a fight and try to win the tie,” he added.
“If we’re playing well and they don’t have a good day, it can happen, like against Villarreal.”
”We are athletes and professionals. It’s a classy thing for a club to do,” he added. “I’m calm and excited. If we’re at our best, we can win the tie.”