Justin Gatlin crosses the finish line to win the 100 meters at the Prefontaine Classic on June 2. (Craig Mitchelldyer/Getty Images)

Justin Gatlin had a bounce in his step as he walked through the Hilton downtown, spotting an old friend and exchanging hugs.

“You gotta see my little man,” Gatlin said with a smile. “He’s two now.”

Gatlin is at the U.S. Olympic track and field trials for the first time since 2004, and he’s just as confident now as he was then. Gatlin, who won gold at the Athens Games, watched the 2008 trials on television, banned from the sport for using performance-enhancing drugs. Now 30 years old, a father, and most likely on the backside of his career, he’s as hopeful as ever.

“This is my first time being really excited — almost kid-like — in a very long time,” Gatlin said Thursday. “It feels good to be back at the Olympic trials. I love the pressure.

“I’m a little older, but also, I think, a little wiser, a little grittier and ready to run.”

Though the field of American sprinters is competitive, featuring Walter Dix and Tyson Gay among others, Gatlin’s recent performances have raised expectations for him here. He has posted the fastest 100-meter time of any American this year.

“Justin is a very emotional runner,” said Dennis Mitchell, his coach. “His emotions are on a high right now. When his emotions are that high, there’s nothing that he thinks he cannot achieve.”

Gatlin will compete this weekend in the 100 meters, the event that brought him fame and gold in Athens nearly eight years ago. Returning to the Olympic stage would be the culmination of a journey that has been all peaks and valleys the past eight years — with very little in between.

“It wasn’t just one journey for me to come back,” he said. “It was more of a parallel journey of two.”

Gatlin served out his four-year suspension and returned to competition in August 2010. He had to return to form physically, he explained, and also mentally build up his confidence. Neither was easy.

If there’s any benefit to be derived from a four-year break, Gatlin says, it’s the appreciation he has today. Until his suspension, Gatlin had never considered any alternative to running.

“My life revolved around track and field ever since I was in high school,” he said.

He was a two-time state champion sprinter in Florida and received a full scholarship to the University of Tennessee, where he competed for two years before turning pro.

“I didn’t have any time to really grow as a person,” he said, “as Justin Gatlin.”

Banned from the track — Gatlin maintained that he never knowingly used an illegal substance — the sprinter said he had to consider how he would pay bills, what he would do with his time. He tried out with NFL teams in 2006, ’07 and ’08 but never signed a contract. He appeared in the reality sports program “Pros vs. Joes.” He served as a volunteer coach for his former high school track team in Pensacola, Fla.

Mostly, he waited to be reinstated.

His comeback has seen a string of improved times. He finished second to Dix at the 2011 U.S. Championships, posting a time of 9.95 seconds. He failed to reach the finals at the world championships, and his times still lagged well behind his best performances.

Gatlin parted ways with his coach, Brooks Johnson, and began working last fall with Mitchell, the three-time Olympian who won gold in the 4x100 relay at the 1992 Olympics. The two spent little time talking about the lost years on Gatlin’s resume.

“When I brought Justin into my camp, we started focusing in on where he was on that day, and we focused on where he wants to be,” Mitchell said. “We understand that Justin has some good and some bad things in his past, but that’s not something that we bring to practice every day.”

Both runner and coach agree there was a lot of room for improvement. Gatlin said he weighed at least 205 pounds a couple of years ago and walked around at 198 pounds just last season. “I was on a strict Jagerbomb diet,” Gatlin joked, referring to the cocktail.

He wasn’t out of shape; he just wasn’t in track shape. Gatlin had been training with football players, lifting heavy weights and eating the wrong foods.

Mitchell prescribed a lot more fruits and vegetables, and Gatlin says he’s currently 182 pounds, the same weight at which he competed in 2004. Gatlin began the 2012 season running a 9.87 in Qatar, topping Jamaica’s Asafa Powell and putting his name back in the Olympic conversation. While that race replenished his confidence, Gatlin says he’s posted better times in practice and plans to run faster still at these trials.

While he’s heard the word “redemption” tossed around plenty, Gatlin looks at his comeback and this Olympic cycle differently.

“For me, it’s almost like a welcoming home party,” he said. “I don’t think anybody really had the expectation of me coming this far. Just to come back and being able to compete was a victory in itself.

“Where I am, going into the Olympics, making this team — knock on wood — I can say that I’m victorious. I’m happy to be back. Of those other seven guys on the line, I know what my worth is to be a USA Track and Field athlete. I know what it feels like to have a talent and not be able to use it for almost half a decade. I think my life in track and field and what I do successfully is very special to me now. Even more.”