A gold medal winner fell flat on her face, ending her chances of returning to the Olympics and her career in the span of 30 seconds. Fresh young faces rose to the challenge, forming a new group of American icons. The fastest man in the world was not. Two Brits dropped the baton and the ball, dashing their country's hopes in a relay event in a finish reminiscent of years past. Two sprinters learned they would have to take part in a run-off to break a dead heat in the women's 100-meter race -- but one decided to drop out.

During this weekend's Olympic trials, the U.S. team saw some of the most dramatic highs and lows as they squared away who would be leading the country into the London Olympics.

The final day of competition for the women competing for a spot on the U.S. gymnastics team was highlighted by the brilliant performance of Gabby Douglas, who upset favorite Jordyn Wieber to nab an automatic spot on the team. Douglas, surging at exactly the right time, impressed the crowd and selection committee chief Martha Karolyi (who calls her the "flying squirrel") with her soaring routines.

"All of this hard work has definitely paid off," Douglas said, according to the USA Gymnastics website. "I just can't wait to wear those red, white and blue stripes down my back. It felt like a dream come true."

Wieber, seen as a top prospect for the all-around gold medal in London, rounded out the young women who had been widely expected to make up the team for a few months.

"It feels amazing to be an Olympian," Wieber said, according to the USA Gymnastics website. "This is definitely the best day of my life, and knowing that all of my hard work has paid off is amazing. I'm just so proud of each and every girl who competed here today."

But the big name missing in the group was perhaps one of the most popular women in the gymnasium Sunday night: the defending Olympic champion, Nastia Liukin.

Liukin, attempting an extremely difficult comeback, struggled on the first day of competition but really fell apart Sunday night as she took on the uneven bars. Just 30 seconds into her routine, Liukin's fingertips grazed the bar, and she fell straight down to the mat. She lay face-down, with her father and coach Valeri Liukin by her side, her dreams of a comeback destroyed.

After shakily finishing the rest of her routine, she waved to the crowd, knowing this was the last time she would compete in a USA gymnastics uniform. Tears welled up in her eyes as she received an ovation given with the same intensity as when she had won competitions in the past.

"I wasn't really expecting that," Liukin told NBC's Andrea Joyce. "I kind of just had tears in my eyes seeing 12,000 to 15,000 people on their feet cheering for me. It was an emotional, but amazing, way to end my career."

But Liukin noted that she had achieved all of her personal goals at the Olympics in Beijing and was thrilled to cheer on the next generation. And as Douglas, Wieber, Aly Raisman, Kyla Ross and McKayla Maroney were officially named to the team on Sunday night, all of them shed tears of joy and no doubt relief that they had made their dreams come true. Now, their focus will shift toward trying to bring a medal home.

The big action wasn't merely taking place in the gymnasium, either. The trials saw a slew of impressive performances by 17-year-old Missy Franklin, who swims on her high school team back home. Franklin turned in stellar time after stellar time, earning her an intense program at the Olympics that made even Beijing champ Michael Phelps proud.

Franklin qualified in several events, and including the team relays, she'll have a chance to go for seven medals, something no other female swimming athlete has attempted.

''I can't believe I have seven events,'' Franklin told Joyce. ''It's so overwhelming but so exciting. The whole week went really, really well.''

That's the same number of events that veteran Phelps is attempting in London. Phelps, who swore after Beijing he would probably never do such an intense program again,was set up to swim the exact program as four years ago. But on Monday morning, his longtime coach, Bob Bowman, tweeted an announcement that Phelps was dropping the 200-meter freestyle. That will give him the chance to swim for seven gold medals and perhaps preserve some energy.

"This change will allow him to focus more energy on relays for Team USA," Bowman tweeted.

It is surely no surprise to anyone that Phelps and his teammate and friendly rival Ryan Lochte dominated on the men's side of the U.S. trials. Over the course of a few days, the two played a bit of leapfrog in terms of head-to-head wins in semifinals and finals of a slew of events, with Phelps coming out ahead in the end.

"It shows I can do an event program like this at a high level again," Phelps said, noting however that he hadn't performed quite as well as he'd like, including a horrible start during the 100m butterfly final.

Cullen Jones, who took part in the memorable relay in Beijing with Phelps, was hoping he could aim for some individual medals. Jones made a solid showing in the trials, securing his individual spots on the team in the 50- and 100-meter freestyle events.

Speaking of those going for individual medals, perhaps no story was more motivating to watch unfold than that of 45-year-old swimmer Dara Torres. Torres lost the 50-meter freestyle gold in Beijing by the smallest of measures: .01 seconds. So she began training again, hoping to make a record six Olympic teams as a swimmer.

On Monday night, it again came down to one mighty fast length of the Olympic swimming pool. Torres stood on the blocks and smiled before preparing to dive in. She hoped she would be able to redeem that devastating loss in Beijing. But Torres fell short, touching the wall fourth in the 50-meter final swim. She missed the cut by .09 seconds. Jessica Hardy and Caroline Joyce came in first and second, securing their slots to compete in London in the event.

Torres has been a fixture in the pool for the United States since the 1984 Olympics. She looked disappointed and shook her head at the end of the race before waving to the crowd in what will likely be the last swim in a storied career.

"I can leave this knowing I gave everything I possibly could," Torres told NBC's Andrea Kremer after the swim. "I tried the best I could."

When asked what her favorite memory in her lengthy and impressive career would be, Torres didn't pick a swim, or a meet or even winning a specific medal.

"The fact that I hung in there this long ... being in the sport this long," she said.