Natalie Coughlin competes in the 100-meter backstroke in the U.S. Olympic trials in Omaha. Coughlin has won 12 Olympic medals. (Jonathan Newton/The Washington Post)

Natalie Coughlin, a 12-time Olympic medalist who is one of American swimming’s most familiar faces, announced Friday that she would drop out of the 50-meter freestyle at the U.S. trials, ending her chances of making a fourth Olympic team — and likely putting a bow on her international career.

Coughlin, 33, stopped short of saying she is retiring. But in a meeting with a small group of reporters, she called her results — in which she failed to make the final in the 100-meter freestyle and finished a distant eighth in the 100 backstroke — “heartbreaking,” and said she didn’t know what lies ahead.

“I’m not announcing a retirement or anything like that,” Coughlin said. “It means I’m not going to the Olympics. From there, I don’t know. . . . [Swimming] will always be a part of my life, and I don’t really see the point of saying that it’s over because it’ll always be there.”

Coughlin’s 12 medals, including gold in the 100 back in both 2004 and 2008 and another gold in the 4x200 relay in Athens, tie her with Jenny Thompson and Dara Torres for the most among female swimmers. She maintained heading into this meet that those accomplishments were plenty, and that anything she achieved in Omaha — or, if she made the team, next month in Rio de Janeiro — would be a bonus. She reiterated that Friday, saying “anything beyond that is icing on the cake in terms of legacy.”

But she was clearly disappointed in her results here.

“I’ve definitely been off for a few months, and I can’t put my finger on it,” she said. She said she would watch the Olympics on television, but she would not say she will put down the sport, even though she will be 37 when the next Olympic trials are held.

“I absolutely love the process of all this,” she said, “even when it is heartbreaking.”

Clary announces retirement

Tyler Clary, who won the 200 backstroke at the London Games, finished third behind Ryan Murphy, who took his second event of the meet, and Jacob Pebley, Murphy’s training partner at Cal. Clary, though, took a different tack from Coughlin and retired.

“I’m looking forward to turning a page in the book of my life,” he said.

The results mean that none of the four U.S. swimmers who won backstroke medals in London — Clary, Matt Grevers, Nick Thoman and Ryan Lochte — made the team in backstroke this year.

Franklin finds positives

Defending Olympic champion and world record holder Missy Franklin (2:08.63) qualified second behind Maya DiRado (2:08.14) in the semifinals of the 200 backstroke, and acknowledged needing to recalibrate her goals after the disappointment of missing a spot on the team in the 100 back and 100 free. Franklin, 21, will be swimming in a maximum of three events in Rio, down from seven in London four years ago.

“It might be really nice to go to an Olympics and really enjoy the experience instead of swimming so much,” she said. . . .

Lilly King won the 200 breaststroke, qualifying for the Olympics in her second event. Molly Hannis finished .31 of a second behind King to land the second spot. . . .

Anthony Ervin, 35, led all qualifiers in the 50 free with a time of 21.55 seconds in the semifinals, just ahead of Nathan Adrian’s 21.60. Ervin will try to make his third Olympic team Saturday night.