Cristiano Ronaldo was unveiled as a Real Madrid player in July 2009. Even though it was a Monday, 80,000 people turned up at the Santiago Bernabeu stadium to catch a glimpse of the star, which was more than the 62,467 fans who attended that year's UEFA Champions League final between Barcelona and Manchester United at Rome's Olympic Stadium.

A further 10,000 disappointed fans—many of whom had queued for hours in dry, baking late-afternoon Madrid sunshine—were left outside the stadium when the gates closed at 8:40 p.m. The evening felt box office. Ronaldo didn't disappoint. Over the next nine years, he smashed all kinds of records, winning four UEFA Champions League titles and scoring 450 goals for Real Madrid. The club might never see a player like him again.

Now that Ronaldo has gone to Juventus, it seems like something is lost. On the field, Real Madrid is struggling, as it trails Barcelona in the league by seven points. Attendances at the Bernabeu have dropped—only 55,229, for example, showed up for its last home game against Rayo Vallecano, on the day his old teammate Luka Modric was presented with the FIFA Ballon d'Or award.

Real Madrid has been averaging 62,500 fans at home games this season, which is a falloff from an average of 65,824 fans per game last season. The average attendance for La Liga games, however, has increased by almost 8 per cent this season, as supporters enjoy the most competitive title race in years, with, for example, surprise package Alaves in the top five in the standings.

"It's inevitable after a superstar leaves a club—one who has had such an amazing period on the pitch with Real Madrid—that something is lost, but I don't think history will define this last six months as a period where La Liga has lost anything," says Gareth Balch, CEO of Two Circles, a sports marketing company. "Commercially, and sport-wise, it has been very strong for the past numerous years, and that will endure for a number of years to come.

"While data suggests there is a lull in interest at the Bernabeu in attendances, and some consumption data of La Liga on digital properties, it's not something that will sustain. It's just a lull—a cyclical effect after having so many highs in recent years with Ronaldo and his Real Madrid team being so successful. You only have to look at Manchester United, and the torrid time they've had on the pitch in recent years and the continued success they have off the pitch to understand the economic landscape of sport now means that brands endure beyond a few years of difficulty on the pitch."

Joris Evers, La Liga's Chief Communications Officer, argues that the league is greater than one man: "Certainly Cristiano Ronaldo is a great player and he contributed a lot to La Liga and football in Spain. However, La Liga and the clubs that form La Liga Santander are bigger than a single player. The competition this season is very close and very exciting. La Liga has been working for the past years to promote the brand of the league as well as the clubs."

Despite Ronaldo's departure, La Liga announced increases in its broadcast deals over the summer, with spikes domestically (15 per cent) and internationally (30 per cent) compared to the last three seasons, with almost €5 billion guaranteed from international rights over five seasons by MediaPro, starting next season.

"None of our broadcasting partners have brought up Cristiano's departure as an issue to us," says Evers. "We're keen to further grow the La Liga brand and club brands to establish the same kind of notoriety the English Premier League enjoys, which is not leaning on individual star power."

The Spanish league lags behind the English Premier League's bonanza broadcasting deals, and in terms of revenue, the Premier League is 86 per cent larger than La Liga, according to figures by Deloitte (h/t BBC).

It's remarkable given the fact that La Liga is above the Premier League in UEFA's co-efficient rankings, with four Spanish clubs in the top 10 compared to two English clubs, and that the Spanish league has accounted for the last five UEFA Champions League winners and four of the last five UEFA Europa League winners.

It is interesting, as Evers notes, that the Premier League has grown over the last decade despite the lack of stardust in its league. Unlike La Liga, it doesn't have a Leo Messi or an Antoine Griezmann, another recent Ballon d'Or finalist. The English Premier League hasn't, for example, had a Ballon d'Or winner since Ronaldo won the award as a Manchester United player in 2008, which was the last time the league even had a player on the podium.

Football since then has been defined to a great extent by the Messi vs. Ronaldo rivalry. Both players—until this year's interloper Modric won for his exploits with Croatia and Real Madrid—have dominated the Ballon d'Or awards. Their standards—and incredible goal-scoring records—have made La Liga a compelling battleground, and have driven each other on.

They have made the Barcelona vs. Real Madrid rivalry arguably football's greatest derby ahead of historical clashes such as Liverpool vs. Manchester United or Boca Juniors vs. River Plate. That storyline is petering out—with the exception of possible UEFA Champions League clashes—now that Ronaldo has left La Liga for Italy's Serie A. However, Evers is keen to raise the profile of the other 18 clubs in La Liga's premier division.

"A main mission of La Liga is to promote the broad league and to gain awareness for more clubs," says Evers. "Barca and Real Madrid are global brands already. We want more clubs to have broad global awareness and for the league as well. That's a key part of our strategy. We admire how people in places like India, Indonesia and Africa can name multiple English clubs today. Depending on where you are, the list of La Liga clubs people can recall is two, three, maybe four. We need to make that a longer list."

Real Madrid president Florentino Perez always had a frosty relationship with Ronaldo. He made a calculated risk in selling him to Juve, making a profit on the sale of him after nine years of service. Perez decided to bite the bullet and begin the regeneration of an ageing squad (a process that could accelerate next summer).

Ronaldo turns 34 in February. Time waits for no man, and his returns will inevitably decline. However, we are seeing stars in other sports like Roger Federer and LeBron James excel in their mid-thirties.

Commercially, though, Ronaldo's stock has never been higher, although that could change quickly depending on how the rape allegations made against him in October by Kathryn Mayorga in German newspaper Der Spiegel develop, with a Las Vegas police investigation ongoing. He has denied the accusations.

Despite the troubling story, Ronaldo has retained the support of his club, as well as many of his fans and sponsors. No other athlete, according to Forbes, makes as much on endorsements. He has hundreds of millions of social media followers. On Facebook, for instance, he has 120 million; La Liga has 49 million. As the face behind the portfolio of CR7 brands, Ronaldo's earning power—if we refer to the post-playing business career of Brand David Beckham—may not diminish significantly once he retires.

"If you look at all the greatest rock bands or movie franchises of all time, the 10th album or the 10th movie always does better than the first one or the second one," says Balch. "With the familiarity and the depth of engagement that can only be accrued over time and over a career in a sporting context—or through a lifetime in terms of, say, a movie-making perspective—it's more lucrative at the back end of a career.

"Therefore, two years of Ronaldo at Juventus is going to beat the early years he spent at Manchester United every day of the week in terms of financial return Juve will get. It's a compound effect you get from the sense of belonging and following he builds up over the duration of a sporting career."

In the summer of 2017, La Liga sensationally lost Neymar Jr. (another global sporting brand) to Ligue 1 side Paris Saint-Germain. Last summer, it lost Ronaldo. The Spanish league will endure, though, without them. The skies did not, for example, cave in when the iconic basketball player Michael Jordan retired from the Chicago Bulls in 1999. The NBA is stronger than ever.

"It's a chicken or egg scenario," says Balch. "Do you become a big league because you have superstars? Or do you present the league well and superstars get born out of it? I think [the latter] is the greatest challenge for La Liga. They've had the most golden period they could ever have imagined—with two of the greatest footballers of all time playing at the peaks of their powers for the two biggest teams, creating the greatest rivalry for the last 10 years or so. It's made for commercial growth.

"But that didn't propel the league to a No. 1 position. It would show you that going and finding another Ronaldo isn't the only way to make the league the world's biggest league in the world. They need to market better and promote it in a way that drives global consumption. That requires a different approach. The next Ronaldo will come along cyclically. If you look back over the last 50 years there has always been great footballers playing in La Liga. The greatest players have always wanted to play at the Bernabeu or the Nou Camp."

Follow Richard on Twitter: @Richard_Fitz