Athletic go to Atletico with both teams in the top four.
"We have a great challenge ahead," Valverde said at his pre-match press conference. "We have to play a perfect match in every way. We can't make any mistakes because Atletico will make us pay for them dearly."
"They're a strong team at home and contenders to win a lot of things. They are in good form and they know it.
"They have a lot of strengths, they have a good attacking game and a good combination of footballers who play well in space. They have the fewest goals conceded in the league and they're the side that gets most points towards the end of matches. They're always competitive."
He added, "Being excited is always good.
"But I'm only focusing on winning the next match. That's what it's all about."