There was never any real doubt Cristiano Ronaldo would keep on doing what he does best after trading Real Madrid for Juventus during the summer.

The €100 million the Turin club parted with is an astronomical sum for almost any player on the wrong of the 30-years-old - except the Portuguese forward, of course.

That said, a three-match wait for his first competitive goal in a Juve shirt prompted some to believe he would struggle to adapt to the more defensive style of Serie A.

But in typical fashion, Ronaldo has shattered all reasonable doubt that his time at the pinnacle of world football is anywhere near over.

The 33-year-old opened his account with a brace against Sassuolo midway through September and has gone on to reach a total of four goals and four assists in nine outings.

Juve have already established a six-point lead of Napoli on the league table, underlining the likelihood of Ronaldo adding a Scudetto to his three Premier League titles and two La Liga crowns.

However, there’s still no clear consensus as to why he left Los Blancos after playing such a vital role in a hugely successful nine-year spell that included four Champions League trophies.

Roberto Carlos - who also won everything on offer during his time at Madrid - believes Ronaldo has earned the right to keep his reasons to himself.

Speaking at a promotional event for the FIFA Club World Cup, the former Brazil international told reporters, per Goal: “It is a decision that the footballer takes.

“He was playing for Real Madrid and we want to thank him for what he did for the club.”

Considering Madrid’s struggles under new boss Julen Lopetegui, many fans have cited the club’s failure to replace Ronaldo as the source of their woes.

It should hardly be a surprise when the club made such a huge amount off his sale, really.

CARLOS ON MADRID'S TRANSFER ACTIVITY

For Carlos, however, his former employers made the correct decision between signing one Galactico or several high-quality players in Thibaut Courtois and Mariano Diaz among others.

“In football, there are so many great football players like Eden Hazard, Roberto Lewandowski and Neymar. Real Madrid are always after the best talent,” he said.

“At the club, there are some very good footballers even after Cristiano Ronaldo left. The president Florentino Perez stays calm and doesn’t rush to sign players for the sake of it.

“It is up to the club if they want to sign a player and it is important they identify players who can fit into the team’s style of play. If they find a player, then they will have to make a decision to try and sign him.”

Madrid are currently fourth and trying to snap a four-match winless streak - hardly an ideal run of form with El Classico just over a fortnight away.

Only time will tell if Lopetegui can get his men back on track without Ronaldo to lead them.