PARIS (CNN) – If world rankings told the whole story, you’d think that Novak Djokovic’s slump shows no signs of easing. But the pure statistics might just be blurring the picture for the struggling 12-time grand slam champion.

Even though the Serb found himself outside of the top 20 this week for the first time since he was a precocious 19-year-old in 2006, his last outing on a tennis court suggests a brighter future. And, with the French Open starting Sunday, the upturn may well continue some five kilometers west of the Eiffel Tower.

Indeed, Djokovic said that spirits are high heading into Roland Garros, the grand slam that he conquered in 2016 for the last of his major titles. “Looking back two or three months, this is the best that I’ve felt on the court, by far,” Djokovic, who just turned 31, told reporters at the Italian Open on Saturday after testing heavy French Open favorite Rafael Nadal before losing the semifinal 7-6 6-3.

Rome is dubbed the Eternal City, and when Djokovic claimed the French Open to become the first man since Rod Laver in 1969 to win four straight grand slams, it felt like his dominance would last forever. His peak level arguably usurped his two main rivals at their best, Nadal and Roger Federer, against whom he still holds winning records.

However, what he called “private issues,” an injury to his serving elbow that required surgery this year and seemingly a shift in attitude — the ruthlessness on court vanished — all contributed to the unexpected downturn.

“The fact that he was machine-like at his brilliant best, it was the total of hours, thousands and thousands of hours of practice,” six-time grand slam winner Boris Becker, part of Djokovic’s coaching setup in his heyday, told CNN Sport. “If you haven’t done that for a year or even longer, then ultimately, even though it’s Novak Djokovic, a perfectionist, he will look ordinary.”

“And I think it’s not that easy being the best,” Becker added. “You have to do a lot of sacrifices, a lot of repetition, a lot of work, and that’s why only a few reach the summit.”

Djokovic only won two small tournaments in 2017 — his last title was last July — and he has failed to exceed the quarterfinals at a major since the 2016 U.S. Open. This March, he fell in the second round of both Indian Wells and Miami, two of tennis’ most prestigious events, which he has won a combined 11 times.

“I saw the matches in Miami and Indian Wells, and I was a little bit worried,” said Becker.

Something had to give — and it did for the man dubbed ‘Superman’ in Serbia. Djokovic ended his partnership with tennis legend Andre Agassi in April. Out, too, went the flamboyant, former world No. 8 Radek Stepanek as his coach. Instead, he reunited with long-time coach Marian Vajda, as well as fitness trainer Gebhard ‘Phil’ Gritsch.

Djokovic’s relationship with Agassi had seemed an ideal fit since the American sustained a similar dip in his career before undergoing a renaissance that included three Australian Open titles. Melbourne was Djokovic’s stronghold through 2016. Agassi has also helped thousands of underprivileged children to get an education in Las Vegas, where he resides, and Djokovic’s foundation assists preschool aged children.

When Djokovic confirmed the coaching changes, days later on his website, there was praise for Stepanek yet barely a mention of Agassi. The 48-year-old Agassi said in a statement to ESPN that the pair “too often found ourselves agreeing to disagree.”

“I don’t know anything that went on, but you have two of the greats who have every right to have strong views about the game and how to go about being one’s best,” Todd Martin, another ex-coach of Djokovic’s and Agassi’s former Davis Cup teammate, told CNN Sport.

“You’ve got west at the ‘nth’ degree coming from Vegas and the east,” Martin continued. “And then you have lives. Andre has forged an amazing life for himself, both with his family and with his work in education. If they agreed to disagree, that’s a big sacrifice and that doesn’t make any sense for someone like Andre.”

An interview request made for Agassi by CNN was declined by one of his representatives.

Djokovic and Vajda, meanwhile, share a close bond. Martin saw it in the eight months that he spent coaching Djokovic with Vajda beginning in 2009. “Marian has been there for him through thick and thin from a very early age, and their relationship is father-son, older brother-younger brother, uncle-nephew, and everything in between,” said the twice grand slam finalist.

“There’s a lot of emotion in that relationship,” Martin said.

Becker was “happy” to see Djokovic’s old gang back, although he ruled out his own return. Now the head of men’s tennis in Germany and a mentor to world No. 3 Alexander ‘Sascha’ Zverev, he said, “I don’t read a very, very good book twice.”

Novak Djokovic

Serbia’s Novak Djokovic hits a return to Spain’s Rafael Nadal during their semifinal match at Rome’s ATP Tennis Open tournament at the Foro Italico, on May 19, 2018 in Rome. (credit: FILIPPO MONTEFORTE/AFP/Getty Images)

Despite the promising showing in Rome, a French Open rematch against an in-form Nadal is a different proposition. However, in his pomp, Djokovic tormented Nadal. He compiled a pair of seven-match winning streaks against the Spaniard. And, although he faded in the second set in Rome, Djokovic believes there was little to separate him and the ‘King of Clay.’

“I don’t think that there was too much of a difference, which is great for me, because Rafa is, of course, the best player ever to play tennis on clay courts,” said Djokovic. “I thought the level of my tennis was very high.”

Martin doesn’t discount a Djokovic run past the quarterfinals in Paris, assuming that he benefits from a gentle start to the fortnight. “I think the resiliency on the physical side, which leads into the resiliency of the emotional side of things, will dictate his success,” said Martin. “If he can win his first nine out of 10 sets or similar, then I could see him doing a little bit better” than the last eight.

Becker said that a quarterfinal result in Paris would mark a “total success.” Anything more and it’s a “breakthrough.”

“I wish him nothing but the best,” said Becker. “If he plays against anyone, I want him to win — except Sascha Zverev.”

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