Juventus won Serie A for the fifth season in a row without kicking a ball on Monday after Napoli, the only team who could have caught them, were sunk 1-0 by a late Radja Nainggolan goal at AS Roma.
Juventus, who have led the table since beating Napoli 1-0 in February, were left with an unassailable 12-point lead with three games each left to play as they clinched a record 31st league title.
The match, played at a half-empty Stadio Olimpico on a sunny bank holiday afternoon, was an anti-climatic end to a season which had at one stage promised to be one of the most exciting Italian title races for years.
The game between Serie A's two highest-scoring sides was threatening to peter out into a tame goalless draw until Nainggolan slotted the ball home in the 89th minute following a move started with a delicate pass from Roma substitute Francesco Totti.
During the first half of the season, the lead had changed almost weekly with AS Roma, Napoli, Inter Milan and Fiorentina all taking turns at the top.
But, as their rivals faltered, Juventus, who beat Fiorentina 2-1 on Sunday, put together an astonishing run in which they took 73 points out a possible 75 to win the title with games to spare.
Roma had more possession but Napoli, whose top-scorer Gonzalo Higuain returned after a three-match ban, carved out the better chances and Jose Callejon had a first-half goal ruled out by a hairline offside decision.