The Russian Premier League champions were ordered to close part of the Khimki Arena for their next UEFA Champions League home fixture with Bayern Munich, after being reprimanded for alleged racist chants towards Manchester City midfielder Yaya Toure.
But Slutsky - whose side are set to battle Manuel Pellegrini's men in the reverse fixture at the Etihad Stadium on Tuesday - said he was unaware of any such incidents.
"We did not hear any racist slur so it is difficult to comment," he said.
"The club is categorically against racism, but we think the situation has been exaggerated and that there has been an overeaction.
"We have received our punishment, it was up to UEFA."
CSKA head into the fixture with City having taken just three points from as many Group D fixtures, and a loss in Manchester would all but end their hopes of reaching the round of 16.
Slutsky will be without defender Vasily Berezutsky for the crucial encounter, after he lost his race to recover from a knee injury.
Attacking midfielder Alan Dzagoev (hamstring) and full-back Mario Fernandes (knee) also remain absent.
Pep Guardiola issues a very blunt answer when quizzed by reporters on latest accusation levelled against Manchester City
'I think my opinion is more important than Roy Keane's. I know as a captain he does things sometimes with his arms, criticising his team-mates, but most of all it's a bit of frustration.' - Ruben Amorim hits back in Bruno Fernandes row
