A 1-0 loss to Tottenham at Wembley on Wednesday saw Inter slip behind Spurs and down to third in Group B , substitute Christian Eriksen netting the winner 10 minutes from time.
The Inter boss thinks the quality the Catalan giants possess and the fact they have not lost a Champions League match at Camp Nou since May 2013 boosts the Nerazzurri's chances, but getting a win against PSV at the San Siro is his sole worry.
"I am convinced that if we do what we have to do, we shall go through. I am convinced that it still depends all on us," said Spalletti.
"I know there are champions over there [in Barcelona] that are competing to win the Ballon d'Or and that are competing to get as many wins as possible. I know that Barcelona have not lost a home game for the last five years, these are the statistics I am aware of.
"But I keep on saying that we need to do what we need to do, which is to play and win against PSV. Then at the end of our match I will ask what the score of the other match was, but we need to win our game. Before I think about the others I want to focus on our own game.
"I want to play that match with confidence, because if we win we stand a good chance of qualifying, in my opinion."