Michael Phelps will take another small step in his comeback to competitive swimming when he competes in two races on Friday but this time he will do it without the presence of his friend and greatest rival.

The 28-year-old Phelps competed for the first time since retiring after the LondonOlympics when he plunged back into the pool at a Grand Prix meet in suburbanPhoenix last month.

He was narrowly beaten in the 100 meters butterfly by Ryan Lochte, his uber-competitive team mate who Phelps credits for driving him to greater heights.

That loss only helped the competitive juices to start flowing again in an ominous warning to his rivals that he has his heart set on greater goals.

On Friday, Phelps will again compete in the 100m fly at a Grand Prix meet inCharlotte, North Carolina, but without Lochte, who is taking a break to overcome a minor injury.

Phelps will also compete in 200m freestyle, an event he won at the 2008 Beijing Olympics when he captured a mind-boggling eight gold medals, but dropped from his program for London.

Phelps has not said what his long-term plans are this time, insisting he is simply testing the waters to see if he still enjoys the grind of training, but he has not ruled out the possibility of competing at the 2016 Olympics in Rio.

As the most decorated Olympian of all time with nothing to prove, Phelps is unlikely to take on another massive program but could still add to his golden stockpile with a reduced schedule.

Although he was beaten in the 100m butterfly in Phoenix, he did enough to qualify for a place at this year's U.S. National championships in California, which double as the selection event for next year's world titles in Russia.

The 100m butterfly is one of two individual events that Phelps won at three successive Olympics. And if he qualifies for the event at Rio, he will automatically make the U.S. men's medley relay team, which has never been beaten at the Olympics.

Phelps is unlikely to swim the more grueling 200m freestyle at Rio but would be an automatic pick for the 4x200m relay team, as long as he qualifies.

He faces stiff competition winning the 200m freestyle at Charlotte against a field that includes reigning Olympic champion, Yannick Agnel of France, who now trains with Phelps in North Baltimore.

But results matter very little in the early stages of his comeback and a qualifying time for the nationals could be all that Phelps wants for now.

Despite his staggering achievements, Phelps and longtime coach Bob Bowman have always been coy about revealing their plans and nothing has changed.

They have still not said when he will race again after Charlotte, saying only that their next plan was to head to Colorado for intense high-altitude training.