SAN JOSE (CBS / AP) — Nastia Liukin rolled through the first 30 seconds of her uneven bars routine Friday night, displaying the form that helped make her an Olympic champion in Beijing four years ago.

Only, it’s not four years ago. And Liukin knows it.

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Needing a big night to show U.S. women’s team coordinator Martha Karolyi she is ready to contribute in London next month, Liukin and her weary shoulders instead faltered at the gymnastics trials. Her dreams of becoming the first defending all-around champion to return for the next games since 1980 vanished along with it.

Liukin posted a score of 14.050 on her signature event, better than the national championships three weeks ago but nowhere near where it needs to be to nab one of the coveted five Olympic spots.

“(I was) running out a little bit of steam, that was basically it,” Liukin said. “I felt like I had a better routine all around besides the very end of it.”

Maybe, but the 22-year-old knows the finals on Sunday will likely be the last time she suits up in competition.

“I was at the peak of my career four years ago and if anybody would have ever told me in 2008 that you would have been competing in the 2012 Olympic Trials I probably wouldn’t have believed them,” Liukin said.

Maybe because returning was never really part of the plan. Liukin took a sabbatical after the 2009 nationals before deciding to make a comeback last summer. She could never quite get healthy while training with shoulders shredded by two decades of gymnastics.

Liukin refused to make excuses, saying if she would have started training earlier her shoulders might not have withstood the abuse. Though she was visibly disappointed after her bars routine, she gamely hopped on the beam 10 minutes later and posted a 14.5.

“I could have just scratched after bars and said, ‘I’m finished,”’ Liukin said.

She didn’t, and patiently answered question after question in the aftermath and has no plans to skip out on the finals.

“I was taught at a young age by my mom and dad to never give up and that’s what I’m going to do, I’m going to finish what I started,” Liukin said.

Her father and coach Valeri stood quietly off to the side watching his daughter talk about a career that has taken her to the greatest heights.

“I’m sure she wants to cry right now, I’m sure that will come later,” he said. “She’s very tough. Very strong.”

SAYING GOODBYE: Bridget Sloan knew her chances of making a second Olympic team were long at best. One miscue during warm-ups never gave her a shot.

The 2009 world champion was scratched less than an hour before competition began due to a sprained elbow suffered when she missed a release on bars and slammed into the mat.

“As soon as I landed you know my elbow hit, it kind of ricocheted off the mat and when that happened I knew something wasn’t right,” Sloan said.

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The 20-year-old attempted to get back out there, but when she went through another warm-up set the elbow started to throb and that was it.

“I noticed every time my arm would move, I could feel something going into my hand,” Sloan said. “It was hard to accept.”

Sloan will undergo an MRI on Saturday to assess the damage and vowed to keep going. The Pittsboro, Ind., native deferred enrollment at Florida to take one more shot at making the Olympic team. She remained an amateur after winning the all-around three years ago and now has a scholarship awaiting her.

“I’ll head down to Florida and have a great time, I will win NCAAs,” Sloan said. “I plan on going down to school and taking names.”

MARONEY RETURNS: If McKayla Maroney had any jitters about returning to competition less than three weeks after suffering a scary concussion at nationals, it didn’t show.

The world vault champion posted the highest score of the night on her best event (16.1) and added a solid 15.2 on floor to remain very much in the mix for the Olympic team.

“I knew that I was going to be in the top for vault, so that was definitely something I had planned because that was definitely a goal coming out here,” Maroney said. “I knew that I had to hit vault because that’s the most important thing if I want to make the team.”

Maroney looked no worse for wear in her first night back after a frightening mishap while warming up for the finals in St. Louis on June 10. The 16-year-old over-rotated at the end of a tumbling run and slammed into the floor, suffering a concussion and a nasal fracture. She was kept out of training for a week, but the layoff didn’t seem to be an issue.

Still, Maroney understands she needs to clean up her beam and bars routines. Neither score finished in the top 10.

“I hope to come back on Sunday and hit everything and just be more confident,” she said.

MIKULAK HURTING: Sam Mikulak’s big night during preliminaries at the U.S. men’s gymnastics Olympic trials came with a big price.

The 19-year-old spent Friday icing down his left ankle after a painful finish on vault during the final rotation on Thursday. Mikulak posted an overall score of 91.8 — the highest of the night — but took a step out with his left foot while trying to stick the landing.

Stephen Mikulak, Sam’s father and an orthopedic surgeon, said his son was “doing well,” but added the ankle has been bothersome since Sam broke both of his legs just above the joint at a meet in Puerto Rico last summer.

Mikulak wore walking boots on both of his feet for several weeks after the injury and took his time rehabbing, though his father said “it never had a chance to get better.”

Stephen Mikulak said his son was undergoing a series of “soft tissue mobilizations” on Friday while taking anti-inflammatories to help deal with the swelling and the pain. He is expected to compete in the finals..

“He landed a little bit short,” Stephen Mikulak said. “They haven’t had a chance to protect (the ankle) as well as they need to. It’s just a little more fragile.”

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