Juventus have won an eighth consecutive Serie A title with victory over Fiorentina last night.
Massimiliano Allegri’s side, who failed at the first attempt with a 2-1 loss at SPAL last week, fell behind after a Nikola Milenkovic opener.
Alex Sandro equalised with a brilliant flicked header in the 37th minute.
Victory was sealed after the break when German Pezzella diverted Ronaldo’s cross into his own net.
“I’m really happy that I have won the Italian title in my first season,” said Ronaldo.
“Of course, it did not go well in the Champions League, but there is next year.”
Juventus’ 35th league title means the Portuguese forward, who signed from Real Madrid for £99.2m last summer, has become the first player to win domestic titles in England, Spain and Italy.
The Old Lady – as they are commonly known – were knocked out of the Champions League by Ajax in midweek and have won every Italian league title since moving to the Allianz Stadium in 2011.
Earlier on Saturday, Juventus Women beat Verona to retain their Serie A Women title.