The two-time Beijing medalist was picked for the U.S. men's gymnastics team for the London Games on Sunday, joined by Jake Dalton and Sam Mikulak. Danell Leyva and reigning national champion John Orozco automatically qualified for the five-man squad after the conclusion of Olympic trials Saturday night.
Chris Brooks, Steven Legendre and Alex Naddour are the alternates.
Horton gives a veteran presence to the deepest U.S. Olympic team in recent memory. The 26-year-old helped the U.S. win a team bronze in Beijing four years ago, then added a silver medal on high bar. None of the other four members are over 20.
"Super excited to be doing this again," Horton wrote in a text to The Associated Press. "I was worried, but I think this team is going to be great."
Mikulak, the 2011 NCAA champion, earned a spot despite spraining his left ankle on vault during the opening night of trials last Thursday.
The injury limited Mikulak to just one event Saturday -- pommel horse -- but his steady rise over the last month was enough for the five-man selection committee to award him a spot. Mikulak was third at nationals in St. Louis three weeks ago and posted the highest score during preliminaries Thursday, his 91.8 just enough to edge Leyva's 91.7.
Mikulak will undergo intense rehab and likely won't be able to do full routines on floor or vault for two weeks. He will join the rest of the team at training camp in Colorado Springs, Colo., from July 8-11.
"YESSSSSS!!! I love today," Mikulak tweeted moments after the team was announced. "Thank you everyone, friends, fans, and my great family! Olympics and London bound here I come."
Dalton, the reigning NCAA champion, gives the U.S. someone who can put up eye-popping numbers on floor and vault. The 20-year-old won both events during trials easily, his explosiveness on the floor leaving Brooks to joke he was "disgusted" watching Dalton's powerful tumbling runs.
Horton makes the team nine months after ripping up his left foot at the world championships in Tokyo last October. The two-time U.S. champion finished third at trials and his steadying presence should help calm any lingering nerves as the U.S. prepares to take on longtime powers Japan and China in London.
Leyva, Orozco, Dalton and Horton were all members of the bronze-medal winning team at worlds last fall, with Leyva taking gold on parallel bars. The dynamic 20-year-old Cuban-born Leyva said a team Olympic gold and an all-around gold are next on his check list, though there's little doubt which one matters most to team organizers.
The U.S. hasn't claimed the top of the podium in the games since Los Angeles in 1984. The Americans head to London with the ability to put up impressive numbers in five of the six rotations. Pommel horse remains an issue, though Orozco and Leyva are much improved, and Mikulak is more than serviceable when completely healthy.
Men's team coordinator Kevin Mazeika insisted he was focused on a team gold and acknowledged the decision to trim Olympic rosters from six to five made the process particularly difficult for a program that's as good as it has been in a generation.
The goal is to compose a roster designed to excel in the team finals, where three gymnasts compete on each apparatus, with all three scores counting. It leaves little room for error but Orozco and Leyva have been rock steady over the last year.
The narrowing of the rosters likely cost Brooks a spot. The affable 25-year-old struggled during preliminaries Thursday, at one point flying off the parallel bars then taking out his frustrations in a nearby hallway. He roared back into contention Saturday and ended up tying Dalton for fourth. Considered more of an all-around gymnast than a specialist, Brooks is good insurance if Mikulak's ankle doesn't recover in time for London.