Athletic Bilbao coach Ernesto Valverde expects a tough test against Eibar in Sunday's Copa del Rey tie.
Valverde has no doubts about the quality of their opponents.
He said, "It's a single-legged tie and one of the two teams will go out.
"They're a team with considerable potential and have the emotional impact of playing at Ipurua. It's a special tie, but a very complicated match for us.
"We don't consider ourselves favourites. It's an open tie in which the lower-ranked team plays at home and that evens the playing field.
"Eibar could very well be in the Primera Division, it's a derby and we know what awaits us at Ipurua. We want to stay in the Copa and that means winning.
"They know what they want to do and they do it well. They started the season with bad results, but by persevering with their style they've improved.
"Now they are on a slightly worse run, but they are still playing well. They are powerful through the middle, they play out from the back and they take their chances."
