Nardi, 21, offered resistance in the first set and managed to escape the first five break points he faced.
But it was not long before Sinner asserted himself.
Eventually taking his seventh opportunity to clinch the breakthrough and capture the first set, Sinner carried that momentum into the second as he raced into a 3-0 lead.
The gulf between the players became increasingly apparent as the match wore on, with Nardi unable to live with Sinner’s devastating combination of pace, power and precision hitting.
While the second set lasted less than 40 minutes, the third barely stretched beyond 20 as Sinner sealed victory with a third-set whitewash.
Sinner ended the match with 28 winners compared with just 17 unforced errors as he demonstrated why he has reached at least the quarter-finals at Wimbledon for the past three years.
This performance was achieved despite his only pre-Wimbledon grass-court tournament at the Halle Open being cut short by a surprise second-round loss to Alexander Bublik.
But, after his devastating defeat by Alcaraz in Paris, in which he squandered a two-set lead and three championship points in a five-and-a-half-hour epic, Sinner has announced his arrival as one of the title favourites at SW19.