Italy boss Antonio Conte called for more respect for Andrea Pirlo despite the decision to leave him on the bench in a 1-0 win over Bulgaria.
Pirlo, who plays for Major League Soccer's New York City FC, struggled in the Azzurri's previous game, a 1-0 win against Malta.
The two wins have Italy atop Group H -- the toughest in qualifying according to Conte -- and a total of 18 points from eight games.
"What really disappoints me is the lack of respect from some towards an immense player [Pirlo]. He deserves more respect in every way," Conte said. "Pirlo cannot be considered irreplaceable one day and the next ready for the scrap heap."
Conte said the team's focus is now on their remaining two matches -- in October versus Azerbaijan and Norway -- as they look to secure their place in the Euro 2016 finals in France.
"We're not qualified yet, so that has to be the primary focus until it is secured," Conte said. "We have absolutely the toughest group of all. We've put together 18 points in eight games and we still aren't qualified.
"Anyone who thinks this is going to be easy has got it very wrong indeed."
The only other teams to have qualified for Euro 2016 so far are England, Iceland, the Czech Republic and hosts France.