The Portugal international received two yellow cards in Depor's 5-3 defeat to Real Zaragoza last weekend but Oltra does not believe the suspension should have stood after the incidents had been reviewed using television evidence.
He told Marca: "The referees are there to take decisions in the moment and the committees to take them afterwards. Pizzi can't play this game for two stupid things, I am speaking clearly and it strikes me as bad that he can't play for this, but this is the rule and it is what it is."
Oltra though is still confident that despite being in the bottom three his side can turn things around in the coming weeks.
"For sure I could have been mistaken in our approach and decisions looking at the results," he said.
"Everything isn't great, but I believe in the squad, in what I am doing and in the way we play. That we have to improve a few things is evident, above all our numbers, but these numbers you will find with confidence and security in what you are doing."
Javier Camunas is expected to deputise for Pizzi, whilst Ayoze, Carlos Marchena and Abel Aguilar are all expected to return to the starting line-up after missing out through injury in recent weeks.
Levante boss Juan Ignacio Martinez meanwhile believes his side will not be affected by the fallout from their 2-1 defeat to Real Madrid last weekend.
Martinez's men were accused by many of being a dirty team due to the actions of David Navarro and Sergio Ballesteros, who clashed with a number of Real's stars, but Martinez insists their focus is now 100% on Depor.
He told the club's website: "It was an a typical week but the group came together and we have focused on the match against Deportivo. We beat them in the Copa del Rey last season but you could see they were a Primera Division team in disguise. Our players have recovered but this will be a very difficult match."
Obafemi Martins is expected to start despite not returning from international duty with Nigeria until Friday so Martinez is likely to name the same XI that started against the champions last weekend.