The pair both scored in the first half at the Stadio Friuli as Juve's charge towards a third successive Serie A title continued.
Antonio Conte's men sit eight points clear of second-placed Roma with just five matches to play.
But while another league title looks highly likely, both forwards were keeping focused on the job at hand.
"It was a decisive game," Llorente said.
"It was so important for us to win tonight and we're happy.
"We're getting through the games and the distance between us and Roma is remaining the same, so that's great as far as we're concerned."
Llorente's goal was his 14th of the Serie A campaign, with nine since the turn of the year highlighting his improved form.
Giovinco earned a rare start in the absence of the club's top scorer, Carlos Tevez, who continues to battle a thigh niggle.
And he made the most of his chance, scoring his first goal for the club since December.
"It's an important victory, but not necessarily a decisive one," Giovinco said.
"The Scudetto's not in the bag yet.
"I hadn't scored for a while and goals are important for a forward. I'm happy that one arrived on a night like this."
Juventus' next Serie A test comes on Saturday when they welcome the visit of relegation-threatened Bologna.
