And Serie A champions Juventus have swooped to sign the Portugal captain, reportedly paying Ronaldo €30 million (A$47 million) a year.
Ronaldo, 33, reached global superstar status after becoming the world's most expensive player when he joined Madrid from Manchester United in 2009.
During his time at the Santiago Bernabeu, Ronaldo won a host of trophies, including two La Liga titles, and two Copa del Rey crowns.
He helped Madrid to La Decima in the Champions League final with Atletico Madrid in 2014 and played a crucial role in Los Blancos winning the competition in each of the last three seasons.
Ronaldo, a five-time Ballon d'Or winner, will now have the chance to win his third different European league title after completing a shock move to Turin.
Ronaldo will turn 34 during his first season with Juve, but the Portugal captain remains one of the two best players of his generation. His arrival is a statement of significant intent from the Bianconeri. They are not content dominating solely in Italy. They have Europe in their sights.
As well as widening the gulf between themselves and the rest of Serie A, Juve now boast a player who has won the Champions League five times – four of which have come in the past five seasons – and has scored the most goals in the competition. Greater pedigree does not exist.
Emre Can and Joao Cancelo have also signed on with the Bianconeri, while Douglas Costa has joined on a permanent basis and Wojciech Szczesny looked more than capable of taking over from the legendary Gianluigi Buffon with 11 clean sheets in his 17 Serie A appearances in 2017-18.
Add Ronaldo to the mix and it has been a stunning transfer window for the Turin giants.
