MESA, United States (AFP) - Michael Phelps is not aiming to recreate the past, but his low-key return to competitive swimming offered a tantalising glimpse of how the Olympic legend could continue shaping the sport's future.
"I was just kind of literally getting my feet wet again," Phelps said of his return to racing after a 20-month retirement.
But he electrified the modest Mesa Grand Prix with a runner-up finish to Ryan Lochte in the 100m butterfly, and USA Swimming National Team Director Frank Busch is among the many who believe a fifth Olympics at Rio de Janeiro in 2016 is well within Phelps's scope.
"I have absolutely no doubts whatsoever," Busch said. "He comes back after almost two years and is barely out-touched, swims the fourth-fastest time in the world (this year) - how freaky is that?"
While Phelps and coach Bob Bowman will not officially confirm that Rio is on the radar, it is clear that a fifth Olympic bid would not mirror the multiple medal campaigns of Athens, Beijing and London that yielded a record 22 medals - an astonishing 18 of them gold.
"His training is much different. It's actually half and in some cases a third of what he used to do," Bowman said. "He'll never go back.
"What we're doing wouldn't work for 17 swims in eight days but it might work for six or seven swims in shorter races."
Bowman acknowledged that Phelps will have to step up his training to return to the international stage.
He is slated for one of Bowman's notorious altitude training camps and perhaps another Grand Prix meeting in Charlotte next month.
"He has an opportunity if he wants to take advantage of it," Bowman said.
Phelps says this sequel to a storied career is about regaining his joy in a sport which by London had become an obligation.
"I think it's no secret that our last several years together it really wasn't much fun for anybody," Bowman said of the tense build-up to the 2012 Games.
Phelps walked away from London without a backward glance, but after putting on 14 kg and hitting, in his estimation, tens of thousands of golf balls, he found the water was where he wanted to be.
The welcome he received at Skyline Aquatic Center in suburban Phoenix was rapturous, from old rivals like Lochte as well as from rising talents like 15-year-old Michael Andrew, who had never expected to stand on the same deck with his idol.
All sessions of the meet sold out on the day he announced his return and the media presence was five-times that of the 2013 edition.
The demise of his long-time relationship with Speedo has even sparked speculation that his marketing clout could pull his current apparel sponsor, Under Armour, into the swimsuit-making business.
"He has reached superstar status in our society," Busch said. "He just happens to be a swimmer. It's amazing for USA Swimming to have such a powerful figure in our sport.
"What organisation doesn't want to have a Tiger Woods or a Michael Jordan?"