It's unclear exactly which of Belgium's select few chances set Conte off in this particular instance. We should also point out that as far as we know, the only bodily harm that did occur in Monday's game was when Simone Zaza gave Conte a bloody lip while celebrating the first goal a bit too enthusiastically.
The obvious guess would be the big Lukaku chance in the 53rd minute, but that's not certain. The video posted by Corriere della Sera shows the time as the 68th minute, which is right around when Hazard had a couple runs through the middle and got close to setting Lukaku free on goal. Meanwhile, the video making the rounds on Twitter, which I'm pretty sure is the same incident/reaction but with a different time-stamp, show it as a reaction to the Lukaku chance. So the later one is probably a replay of the earlier one. Either way, here's Conte going ballistic.
من مباراة الأمس " ردود فعل القائد بوفون و المستر كونتي بعد هجمة لوكاكو الخطيرة " pic.twitter.com/2JUKHGlasF— الآزوري (@Italy_arab) June 14, 2016
Italy's performance against Belgium on Monday was plenty impressive as Conte's men administered a rather comprehensive defeat on Eden Hazard & Co, but it wasn't perfect. You might argue there is no such thing as a (literally) perfect performance, and the opposition will always get least a chance or two regardless of how well drilled your defense and midfield may be, but when you're Antonio Conte and you pride yourself on your gameplan and tactical setup, you don't take it lightly when your team gives up a chance or turns the ball over in a bad spot.