The goals were scored by Spaniard forward Fernando Llorente (31st and 76th), midfielder Claudio Marchisio (73rd), and Swiss defender Stephan Lichtsteiner (80th).
Cagliari Calcio had scored the first goal, by Chilean forward Mauricio Pinilla (21st), but it was also the only goal scored.
The victory insures Juventus FC the leading spot in Serie A for another week. Juve leads the Italian league with 52 points after 19 rounds. AS Roma trails Juventus by 8.points.
The next game for Juventus FC will be Saturday, January 18, against Sampdoria who is currently struggling in 15th place for round 20.
Cagliari Calcio sits in 13th place and will face Atalanta for round 20 next weekend.