Despite that victory Los Rojillos remain bottom of the table and Mendilibar believes some of the reaction to his side's win has been over the top.
He told the club's website: "The victory changes a lot but we are still last in the table.
"The week has been happier but the situation remains the same. We are last and we are obliged to take something from this weekend.
"Also we are obliged to take something from a match at home."
Mendilibar will be forced into at least one change from the side that started at the Cornella El Prat as Emiliano Armenteros is suspended, but Roland Lamah has returned to full fitness and should start in his place.
Malaga have endured a poor run in La Liga, losing their last two games at home and slipping out of the Champions League places.
Coach Manuel Pellegrini expects another difficult challenge when his side take the road north to Pamplona.
He told the club's website: "I think that no matter where this Osasuna is, it has always been a very difficult place to go to.
"El Reyno de Navarra is a pitch where there is a lot of pressure put on the referees and the team feels home advantage.
"Yes, this year, they have had some important stumbles, but I am sure that we are going to meet a difficult opponent like the one we met last week."
Martin Demichelis and Ignacio Camacho return from suspension for the Andalusians, but full-backs Nacho Monreal and Sergio Sanchez are ruled out through injury and Julio Baptista is still a few weeks away from his comeback after 14 months out.