Fritz is among a handful of contenders looking to end a 23-year American wait for a men's Grand Slam singles champion after Andy Roddick's Flushing Meadows triumph, and the ninth seed has strengthened his position after his first two matches.
"I came out feeling really good. I felt confident with the way I was playing. In the whole match, there weren't many nerves. I was aggressive, and it felt great," said Fritz after his 98-minute demolition job.
"It's fun, playing a match like that on Arthur Ashe Stadium. I don't know if there are many more things better than that; it's a great feeling."
The 2024 runner-up barely gave his unseeded Italian opponent any chances to settle as he dictated terms from the baseline and raced through the opening set in 35 minutes without conceding a game on the main show court.
A timely ace in a tight game helped world number 95 Bellucci open his account in the next set, but it was all Fritz from there as the 28-year-old home favourite reeled off games to double his lead in the match.
Bellucci was unable to alter the pattern of the clash in the third set as Fritz remained in control, sealing another easy win to set up a meeting with 24th seed Francisco Cerundolo and keep his bid for a maiden Grand Slam title on track.