Novak Djokovic, right, had an answer for each of Rafael Nadal’s new strokes and tactics Sunday. (Kin Cheung/Associated Press)

Having established himself as a clay-court master, Rafael Nadal reinvented his game, at age 21, with the goal of winning Wimbledon. His competitive makeover for grass-court tennis — ramping up his serve, altering his footwork and flattening his looping, topspin-heavy groundstrokes — worked to perfection, helping him claim the sport’s most prestigious title in 2008 and again in 2010.

This past offseason, Nadal, at 32, retooled his strokes and tactics again — this time with the goal of playing more efficient, effective tennis on hard courts, the surface that has exacted the harshest toll on his knees over a 19-year pro career.

Until Sunday’s Australian Open final, that makeover had worked to perfection, too; the Spaniard steamrolled through six opponents without dropping a set. Nadal’s first serve was devilishly placed and precise. His forehands were blasted down the line on a rope — a change-up from his go-to, arcing, cross-court shot. And there was far less anguish in his rallies. He was winning points with big-bang efficiency, a radical change for a player known for turning best-of-five-set matches into operettas.

But on Sunday at Rod Laver Arena, Novak Djokovic had an answer for each of Nadal’s new strokes and tactics. Djokovic served better and returned brilliantly, breaking the Spaniard five times in his 6-3, 6-2, 6-3 victory — more times than he had been broken all tournament. Djokovic defended better and attacked more effectively, knocking the muscular Nadal on his heels with lightning-quick, penetrating groundstrokes.

Djokovic rarely placed a ball anywhere but the precise spot he intended, committing just nine unforced errors in the contest. And a matchup that was predicted to be a battle for the ages was over in the blink of an eye, with Djokovic needing just 2 hours 4 minutes to dismantle Nadal.

In becoming the first man to win the Australian Open seven times, Djokovic, 31, extended his tally of major titles to 15, putting him within two of Nadal and within five of Roger Federer’s record of 20. But as wide as the gap was between Djokovic and Nadal on Sunday in Melbourne, the gap between them and the highly touted next generation of men’s tennis players is greater.

Despite their age, Nadal and Djokovic remain atop men’s tennis. (David Gray/Agence France-Presse/Getty Images)

Young phenoms Alexander Zverev, 21; Stefanos Tsitsipas, 20; Denis Shapovalov, 19; and Frances Tiafoe, 21, are ranked in the top 30, showing tremendous promise and building a next-generation fan base, which the sport sorely needs. But their games aren’t nearly as complete, their tactics not as savvy and their Grand Slam intensity not as bloodthirsty as that of Djokovic and Nadal, who demonstrated anew how exceptional they are.

The women’s side, by contrast, signaled that a new era has arrived, with 21-year-old Naomi Osaka backing up her unexpected triumph at the U.S. Open in September to earn a second consecutive major and, with it, take over the No. 1 ranking. Osaka showed fierce tenacity in turning back two-time Wimbledon champion Petra Kvitova in a three-set final Saturday that lasted 23 minutes longer than Sunday’s men’s final. She also became the first woman other than Serena Williams to win back-to-back Grand Slams since Kim Clijsters in 2010-11.

That’s not to say that Williams, 37, won’t win more majors to put her Open era-record 23 even further out of reach. But the Australian Open suggested that the pecking order atop women’s tennis is dynamically in flux, with young players such as Amanda Anisimova, 17, and Aryna Sabalenka, 20, flashing impressive power and grit and familiar faces Caroline Wozniacki, Angelique Kerber and Simona Halep falling short of expectations.

The men’s game, for now, is a crowd of two after revolving around four players — Federer, Nadal, Djokovic and Andy Murray — for the past 10 to 15 years.

Federer, at 37, remains a joy to behold but hasn’t advanced past the quarterfinals of a Grand Slam since he vanquished Marin Cilic in five sets in Melbourne a year ago to claim his 20th major. And Murray, 31, announced on the eve of the Australian Open that this season will be his last because of chronic, debilitating hip pain that a 2018 surgery failed to alleviate.

That leaves Djokovic and Nadal firmly atop the sport.

They are proving better with age. They are wiser about managing the wear and tear on their bodies. They are greedier about each opportunity to embellish their legacy. And though ranked Nos. 1 and 2, occupying the perch that every top-30 player covets, they are continuing to adapt, determined to refine and adjust their skills to fend off the next opponent and all that time inexorably takes away.

With his clinical perfection Sunday, Djokovic cemented his status as the sport’s greatest on hard courts. Nadal, with 11 French Open championships, is firmly ensconced as the King of Clay. Yet both are still chasing Federer’s Grand Slam record and at least a stake in the debate over the greatest of all time.

In his on-court remarks during Sunday’s trophy presentation, Djokovic paid tribute to that quality in Nadal, whom he regards as his greatest rival and the player most responsible for pushing him to be even better.

“You are showing to me and to everyone what is the definition of the fighting spirit and resilience,” Djokovic said. “Thank you for that.”

And Nadal, who was never a threat Sunday, unable to find a solution among his arsenal of weapons, vowed to keep working after his most lopsided defeat in a Grand Slam final.

“I only can say one thing: I’m going to keep fighting hard, keep working hard to be a better player every moment,” Nadal said. “I’m going to keep fighting, keep practicing, [doing] all the things I have to, to give myself a better chance in the future.”