The Bianconeri were defeated at the Stadio San Paolo after Maurizio Domizzi converted two extremely controversial penalties.
"When these things happen, it is quite simply a scandal," noted David Trezeguet as he left the arena.
Vincenzo Iaquinta came on as a late substitute and tried to be a little more diplomatic about the performance of referee Mauro Bergonzi.
"I will not comment on the penalties, I did not see them. Now we have to focus on the next game and get right back on track."
Juve found an unlikely ally in Napoli President Aurelio De Laurentiis, who praised his team but also admitted there had been mistakes.
"Those incidents are not our problem, but they are a problem for the Federation that hopefully will one day decide to use slow-motion replays on the field to make more accurate decisions. Then we'll end it once and for all with this farce that only suits the media," said the movie mogul.