INDIANAPOLIS — Matt Grevers is here for a good time, even if it isn’t a long time. Really, he’s at Lucas Oil Stadium for up to three 22-second races in the U.S. Olympic swimming trials pool. 

The 39-year-old two-time Olympian just couldn’t resist a chance to swim in an NFL stadium. So he came out of a three-year retirement, trained for about six months, qualified for trials and will swim the men’s 50-meter freestyle. 

“I just happened to be in a situation that I could put a little more time on myself and feel selfish,” Grevers said Tuesday. “But once I went the [trials qualifying] time, it felt really good! And it's cool to know that at 39, my body definitely still has it. It’s just, what are you willing to put into it?

“So it was … really fun just to know that I get to swim here [and] hang out with a lot of friends. Walking on the pool deck saying hi to all the coaches and older athletes just felt kind of like a homecoming.”

Grevers has six Olympic medals on his résumé, but individually, he was more of a backstroke specialist. He won silver in the 100-meter backstroke at the 2008 Beijing Games, along with two golds on relays. In London four years later, he was the 100 back Olympic champion and won another gold and silver on relays.

Back for his seventh Olympic trials, Grevers qualified for the meet in May by just .29 seconds, as SwimSwam noted. 

Prelims for the men’s 50 free are Thursday morning, and Grevers is seeded 35th with an entry time of 22.50. He may be only a second behind top seed Ryan Held, but for the fastest event in the pool, that’s an eternity. 

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To swim more than once, Grevers will need to make the top 16 to advance to Thursday night’s semifinal, when the top eight swimmers move on to Friday night’s final for a shot at making the 2024 Paris Olympic team. 

“I love the anticipation of the race, and I'm going to love the race, and this time, it just happens where the outcome isn't as significant as before,” Grevers said. 

“It's not too much race strategy. You don't breathe. You don't have to worry about walls messing up turns. You just jump off that block and go as fast as you can. It’s so pure, raw speed and power.”

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Grevers is the latest older American sprinter to return to the pool and try to make the Olympics. 

Five-time Olympian and 12-time medalist Dara Torres made her first Olympic team in 1984 and her last in 2008, when she won three silver medals at 41 years old. Three-time Olympian Anthony Ervin has a 16-year gap between Olympic golds in the 50 free after winning in 2000 and then again in 2016 at 35 years old. 

Even at trials, Grevers said he’s been inspired by Gabby Rose, a 46-year-old swimmer who finished 10th in the women’s 100-meter breaststroke semifinals Sunday. She also advanced to Wednesday night’s 200-meter breaststroke semi. 

“Gabby's cheer when she went out for semifinals, it was one of the loudest ones of the meet. I was like, so people are rooting for the old guys just to see what you can do.”

At previous trials, making the Olympics was his livelihood, and he said he felt like he owed it to his support system to make the team and win medals. While still grateful for his supporters, particularly his wife, Annie, he said he’s just enjoying himself.

“To be in this environment without that much pressure is super refreshing and just a really great time,” he said. “Watching the finals of the 100 back [Monday] night, I was like, kind of want to be there. And then when they’re stepping up behind the blocks, and I saw faces and a little bit of pre-race anxiety, I was like, ‘I’m happy up here.’ ”

Follow Michelle R. Martinelli on social media @MMartinelli4