The Delfini currently have the dubious honour of sharing last place with Palermo. Both clubs are five points from safety, with Pescara having won just one game since New Year's Day.
A 2-1 loss at Atalanta further weakened Pescara's chances of extending their stay in the top flight to a second season, but Pellizzoli is not ready to throw in the towel.
He told the Corriere dello Sport: "Here we are talking about another defeat but in reality all we need to do is focus on the next game.
"I believe strongly that we will survive and I will continue to do so until the maths condemn us.
"We all have to believe it right until the very end and, although it will not be easy to overcome this difficult moment, we must react immediately.
"Now there's a game against Chievo who are similar opponent to Atalanta - tough and difficult to break down.
"We need to put them under the cosh from the start and stay focused until the end."
Gaetano D'Agostino, Ferdinando Sforzini, Francesco Modesto and Luciano Zauri sit out through injury, while winger Vladimir Weiss serves a one-match ban.
Chievo have not visited the Stadio Adriatico for a top-flight game in over 20 years and are without injured defenders Gennaro Sardo and Francesco Acerbi on their return.
Striker Alberto Paloschi, meanwhile, has promised to get back among the goals as the Flying Donkeys bid to put their hosts to the sword.
Paloschi, who has not scored for five games, said: "There are times when you shoot once and you score but there are others when you have lots of chances but the ball won't go in.
"It will be essential for us to win the Pescara game and move closer to booking our own survival.
"But it's the last resort for them and if they get a result against us they'll be back on track, so we have to prepare ourselves."