Aurelio Andreazzoli claimed even his "four-year-old grandson could see that was a penalty" after he was left furious with the refereeing in Empoli's 2-0 defeat to Inter.
Danilo D'Ambrosio headed in the opener for Inter after 33 minutes but Empoli felt Nedim Bajrami had been fouled at the other end by the Nerazzurri centre-back.
Federico Dimarco subsequently added a second following Samuele Ricci's dismissal for a reckless challenge on Nicolo Barella, leaving Andreazzoli fuming over the standard of officiating in Wednesday's Serie A clash.
"I want to be very clear that I have never talked about referees, because I think they ought to be defended as a profession," Andreazzoli told Sky Sport Italia.
"However, I want to know what exactly Paolo Valeri was doing this evening at the VAR desk. Either he was distracted or he popped to the bathroom or something, because how is it possible that VAR does not help the referee when it has to?
"Let’s leave aside the Inter performance, just like the red card for Ricci, which I’ll admit was basically an orange card and I accept that. I always accept decisions.
"However, if VAR sees a clear and obvious error, I ask myself why do they not help the referee? That is what they are there for.
"Honestly, even my four-year-old grandson Tommaso could see that was a penalty. I saw it on a phone when I went back into the locker room at the final whistle and was shocked when I saw the replay.
"If we do not use these instruments and this technology, then we remove the objectivity of refereeing in games. The matches must be objective. The referee did a good job overall, but he didn’t see that incident, the VAR did, so help him make the right decisions."
Inter managed a seventh consecutive top-flight clean sheet on the road against Andreazzoli's team – their best run against a single opponent in the competition and tied for the best streak of any one side against another.
At the other end, Alexis Sanchez assisted D'Ambrosio's opener - his 21st goal involvement in 23 Serie A starts with the Nerazzurri in Serie A (nine goals, 12 assists) - and Inter's assistant manager Massimiliano Farris was quick to praise the Chile international.
"It’s true that his characteristics are fairly unique within the team, but Joaquin Correa could do something similar if called upon," Farris said post-match to Sky Sport Italia.
"Alexis has that creativity, that moment of magic, you just need to see the assist for D’Ambrosio’s goal.
"D’Ambrosio and Dimarco are added value to this squad and bring more than you’d expect.
"It’s a pity Lautaro Martinez didn’t score today, but he’s saving his goals for other games. We made a few changes, everyone showed they were ready when called upon, as everyone has to work together as a team."