Juventus sealed a seventh consecutive Serie A title with a draw against 10-man Roma.
Second-placed Napoli won at Sampdoria, but a point was enough to give Juventus their 34th top-flight title.
It adds to Wednesday’s Coppa Italia success, meaning coach Massimiliano Allegri has won the Italian double in each of his four seasons in charge.
Roma ended with 10 men at Stadio Olimpico following Radja Nainggolan’s red card.
The race for the Scudetto had looked like going down to the wire when Napoli secured a dramatic late victory in Turin on 22 April.
But a 3-0 reverse at Fiorentina coupled with a 2-2 draw against Torino left the Neapolitans’ hopes of claiming a first top-flight title since 1989-90 in tatters.
Despite leading the table for a large part of the season and accruing 88 points, a club record haul, Napoli needed the Bianconeri to lose both of their remaining fixtures to stand any chance of catching them.
But once Nainggolan had been dismissed for a second yellow card midway through the second period, those hopes were effectively extinguished.
Juventus may not be able to boast the stardust of previous campaigns but they remain a highly efficient unit.
Even without Gianluigi Buffon in goal, they rarely looked like conceding and held out with relative ease to move on to 92 points, four clear of Napoli with one game remaining.