The Belgrade only made eight unforced errors and made the Italian premiere bitter, too nervous, in his first ATP Finals.
In just 62 minutes, Djokovic, who pursues the number one at the end of the year that Rafael Nadal now holds, won his first victory of the tournament and reduced the difference with the Spanish in the ATP classification to 440 points momentarily.
The game, in addition to fast, was devoid of winning strokes and between the two players only added 22, ten for 'Nole' and twelve for the transalpine.
Berrettini, who was the last to qualify for the appointment of 'teachers', noticed the nerves at the premiere and not even his service was a weapon with which to put Djokovic's defense in trouble.
He only connected four direct services, the same as Djokovic, and his percentage of points won with the first serve did not reach 50%.
Given that and an audience eager for the show, who was left wanting, Djokovic had no mercy, swept Berrettini and began his career in the Bjorn Borg Group, which was framed next to the Swiss Roger Federer and the Austrian Dominic Thiem.
In this edition, in addition to the number one, Djokovic seeks to get his sixth Masters Cup, which would match Federer, leader in the winners of the tournament.
The Swiss will debut this Sunday, in the night session, before Thiem. EFE