Andrea Strammaccioni's men won the preparatory event for the eighth time in 12 editions by beating two of their fiercest rivals over three 45-minute matches
It was the Nerazzurri who landed the first blow of the night, beating Juve in the opening 45-minute fixture thanks to a 12th-minute goal from Philippe Coutinho.
The Brazilian took advantage of an error by former team-mate Lucio, who hesitated as the ball took a wicked bounce near the six-yard box, allowing the attacker to fire confidently past Marco Storari.
The Italian champions bounced back with a 1-0 success of their own in their second fixture against Milan. Mirko Vucinic picked himself up to fire home a penalty 14 minutes from time having been brought down in the area by Bakaye Traore.
In the Milan derby decider, Stephan El Shaarawy struck first when he reacted quickest to Kevin-Prince Boateng's knockdown, threatening a three-way tie on results.
But Fredy Guarin headed Inter level from Rodrigo Palacio's pinpoint cross before the provider turned scorer 11 minutes from time to confirm Inter's third straight Trofeo TIM success and their eighth in 12 editions.