Juventus defender Andrea Barzagli was left fuming after the Serie A champions suffered a 1-0 defeat to AC Milan at San Siro.
A stunning strike from Manuel Locatelli in the second half sealed a win for the home side that takes them to within two points of Juve at the top of the table.
The visitors were furious when Miralem Pjanic's first-half free-kick nestled into the far corner, only for the officials to disallow the goal after Milan players had complained about offside infringements from Medhi Benatia and Leonardo Bonucci.
Juve were also denied a last-minute equaliser when Gianluigi Donnarumma produced a fine save to keep out Sami Khedira's drive from distance.
Barzagli felt those were the two key moments in the match and admitted that he was far from happy with the outcome.
"I'm angry we lost. We played better than we have in other games but if you lose 1-0 it means you have to do better," he said, as quoted by the club's official website.
"Still, I think we can say the match turned on two moments today. It was wrong to rule it [Pjanic's goal] out but things like that can happen. It was still 0-0 and we had an hour left to win it.
"Now we have to sit down and look at what we did wrong and keep working hard.
"There are lots of things we need to improve although at the end of the day we hardly afforded our opponents any chances, not even in the second half."