OMAHA, NEB. — When Michael Phelps arrived in Omaha in 2012 to swim at his fourth Olympic Trials, he was acting the part of “happy guy” in a script he barely cared to follow.

The truth was that the best swimmer in the world didn't want to get anywhere near a pool, much less handle the scrutiny that came with being his sport's chief ambassador.

“He didn't want to swim, but he kind of had to,” said his longtime coach, Bob Bowman.

Phelps in 2012 could not have imagined returning to Omaha four years later as a rededicated athlete and a contented new father. But that was the guy who took the stage Saturday for his premeet news conference as he prepares to qualify for a fifth Olympics.

Phelps described the easy pleasures of joking with fellow Olympians Ryan Lochte and Elizabeth Beisel in the warmdown pool Saturday morning, laughs he might have faked four years ago.

“I was actually enjoying myself, and we were telling jokes with one another,” he said. “That's what I didn't have in 2012. That was nowhere to be found. I wanted to get in and out as fast as I could. I wanted nothing to do with it. I think I'm just a lot happier doing what I'm doing now.”

Phelps will try to make the Olympics in at least three events over the next week, and he still expects greatness of himself in the pool. The chief difference, Bowman said, is that he no longer worries where Phelps' mood will go when he's not competing.

The swimmer's fiancee, Nicole Johnson, gave birth to the couple's first child, Boomer, last month. That momentous change followed almost two years of serious self-examination as Phelps recovered from the emotional bottom he hit when he was arrested for drunken driving in September 2014.

“He's living his life well,” Bowman said.

Phelps the swimmer is not the same, either. Gone are the Herculean schedules of his prime, a concession to the fact that his body does not recover as quickly as it once did. Part of his mistake at the 2012 Olympics was attempting the grueling 400-meter individual medley right out of the gate, even though he'd trained haphazardly.

This time around, he'll focus on his three best races: the 200 IM and the 100 and 200 butterfly. He posted the best time in the world last year in each, all part of a commanding performance at the national championships in August.

It was the meet at which Phelps reclaimed the familiar aura as the man to beat after more than a year of uneven performances, interrupted by his DUI arrest, rehabilitation and a six-month suspension from competition.

Phelps is entered in five events at the trials and could swim as early as Monday morning in a preliminary heat for the 200 freestyle. But he's not expected to swim that race or the 100 freestyle as individual events at the Olympics. So if anything, he'd probably look to post times that would put him on the 4x100 and 4x200 relay teams in Rio de Janeiro.

Phelps was typically noncommittal Saturday when asked about the freestyle races.

“I'm pretty much set on what I want to swim,” he said. “You guys will see my first event soon.”

Phelps' first individual final (the top two finishers make the team) is likely to be the 200 butterfly Wednesday night, an event in which he hopes to reclaim Olympic gold after South African rival Chad le Clos beat him in 2012.

He said it's strange to be at the trials without an event to swim for a few days. Friday was downright tedious as he sat in his hotel room with the blinds drawn because he didn't want to stare at the massive image of his face plastered on the adjacent CenturyLink Center.

The 400 IM, a race he used to own, is scheduled for today, the first day of the meet. Bowman joked that he'd sneaked Phelps into the field. But Phelps said he'll be perfectly content to watch his training partner, Chase Kalisz, and his old rival, Lochte, duke it out.

Bowman said he's never quite sure what to expect from Phelps until a big meet begins. For example, he thought disaster was looming before his pupil delivered the greatest performance of his career at the 2007 world championships in Australia.

“It's like a haircut,” a grinning Bowman said. “You don't know how good it is until it's too late.”

But he's been pleased with Phelps' training all year and said there's no reason to think the 22-time Olympic medalist will falter at the trials.

NBC analyst Rowdy Gaines said he'll be watching Phelps on two levels this week. He wants to see whether he's in command of details such as coming off the starting block crisply and moving smoothly through turns. But Gaines also flew in his wife and daughter because he wants to share the experience of watching the best ever.

“He changed the sport more dramatically than anyone in history,” he said. “So I'm going to sit back and enjoy this artist, what he's been able to do.”

Phelps, meanwhile, probably fielded more questions about Boomer than he did about his racing schedule. The littlest Phelps, now 7 weeks old, is scheduled to arrive today with his mother.

His dad talked about the simple wonders of watching a baby gain weight, grow hair and change eye color.

“I've learned which cry means what,” Phelps noted, even though he was away, training at altitude, in the weeks immediately after Boomer's birth.

He provided detailed analysis of the name selection. He and Johnson didn't want something too normal, and Phelps had Boomer in his head after watching former Maryland and NFL quarterback Boomer Esiason on television one day. So he blurted it out.

“Bo or Boo, you can go a lot of different ways with it,” he said of the nickname possibilities.

Bowman noted that Boomer has his dad's long torso and short legs.

“I keep trying to push him into a breaststroke motion,” he said.

Phelps was basically a kid himself when he first swam at the trials in 2000, earning an unexpected berth on the Olympic team as an unknown 15-year-old from Towson.

“It's nuts,” he said when asked whether he's been contemplating the sweep of his career.

Unless he changes his mind again, this week will feature his last races on U.S. soil. If he's back at the trials in 2020, he swears it will be as a spokesman for the sport and perhaps as a coach to the next generation.

But before all that, he faces a few more turns playing Michael Phelps, greatest swimmer ever. This time, he said, it's a role he's happy with.

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