(CNN) Superlatives are never in short supply when talking about MotoGP star Marc Marquez.

In 2013, at just 20 years old, he became the youngest ever rider to win MotoGP's premier class. A year later he won the title again, with 13 race victories -- the most by any premier class rider -- beating a record held since 1997 by the legendary Mick Doohan.

Then, in 2016, he became the youngest rider to win three MotoGP world titles.

This weekend, in Valencia, Spain, the Repsol Honda rider will fight for a fourth premier class title, his sixth across the sport's classes. With a 21-point lead in the standings, he is hot favorite to take motorcycle racing's ultimate prize yet again.

If all this sounds like plain sailing for the 24-year-old Catalan, this season has been anything but. Six races into the campaign he had managed just a single win -- at the Grand Prix of the Americas in Austin -- and had failed to finish in two other races.

"I knew we could have a difficult start [to the season]" Marquez told CNN Sport.

"We had made important changes to the engine and we needed time to understand how it worked, but I always try to be positive."

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'Good feelings'

Positivity flows from Marquez. In person, his infectious grin is only rarely absent. He laughs spontaneously and often. Members of the Marquez family mingle happily with his Repsol Honda team, and the atmosphere in his garage is focused but warm.

"I trust the potential of my team and the factory and I know that they always work hard to achieve the best level possible," he explains. "They have shown one more year that all together we can overcome any situation."

Overcome it they did. From the sixth round onwards Marquez chalked up five race wins and four other podiums, moving up the standings before tightening his grip on the championship.

"The improvements that we've made to the setup during the season helped me to feel so much more comfortable on the bike," he says.

"And when you have good feelings, you have more confidence, and this allows you to push to the limit."

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Formidable Ducati

The surprise this season has come in the form of Ducati and 31-year-old Andrea Dovizioso, who remains in contention ahead of this Sunday's final race. Marquez says the reinvigorated Italian outfit has become a formidable package.

"We all knew that Ducati had a very good bike for certain circuits," he says.

"But what has impressed us this year was that they took a big step in those circuits where they used to struggle more. This shows that they have been working hard to be in front. Lately, when you follow a Ducati, it's hard to see weak points."

The gracious and unassuming Dovizioso is widely liked in the paddock, and that cordiality extends to Marquez.

For fans a new face near the top of the standings has been a refreshing change, but Marquez says he pays little attention to who he is racing against.

"The most important thing for me is to be one of the riders who are battling in front," he says. "Honestly, I don't care if I fight with this or this other rider, I care about giving my best and try to win.

"That said, I have a good relationship with Dovi and I've enjoyed fighting with him in the track this season. He's been a tough opponent."

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Rossi fans have not forgiven

The battle between Marquez and Dovizioso has occasionally threatened to sour that relationship this season, with the world champion's uncompromising style testing its boundaries.

The overall atmosphere, however, is of genial mutual respect. It's a stark contrast to Marquez's battles with nine-time world champion Valentino Rossi, which threatened to tear the championship apart two seasons ago.

The 38-year-old Italian appears to have buried the hatchet with Marquez, but many in his legion of fans have yet to forgive the Catalan for his brushes with "The Doctor," which some maintain prevented their idol from claiming a tenth crown.

It is not uncommon to hear boos when Marquez takes to the podium. Marquez is philosophical about the ongoing rancor.

"I don't know [if the boos will stop]," he says. "It is said that 'time cures all,' but I try not to think a lot about this. I'm focused on my work to do my best and make happy the people who cheer for me which, fortunately, are a lot."

Spain awaits its Catalan king

As a Catalan preparing to race in Spain, there is another interesting dimension to Sunday's race: if Marquez finds himself on the podium celebrating a championship win, will the political turmoil in the country cross his mind?

Perhaps sensibly, the man from Cervera is not being drawn into the debate. "I wish I will be in the podium," he says.

"Because this would mean that we've reached our goal and I would be very happy for that."

One thing is for sure, a fourth premier class title this weekend will see both Spain and Catalonia keener than ever to claim Marquez as one of their own.