LONDON (AP) -- The cruel irony of Brooke Crain laying on the gravel of the Olympic BMX course was that a crash involving a teammate is what allowed her to be there.
The 19-year-old Crain was a late substitute for Arielle Martin, whose devastating fall during practice on July 30 left her in the hospital. Crain ended up joining the five-rider U.S. team headed for the London Games, and was making her seeding run Wednesday when disaster struck.
Crain was poised to post one of the fastest times when she turned onto the final straight, and a bobble on one of the gravel hills sent her flying over her handle bars. Her chest slammed into the next hill and Crain lay there for about a minute while volunteers ran out to check on her.
She eventually got up and slowly rode across the finish line.
"I'm feeling fine," Crain said about 90 minutes later. "I got the wind knocked out of me and a bit of a bruised thigh, but I'm feeling fine."
Crain was given the final seed, which is used to determine the start list and gate selection for the semifinals. In the women's competition, there are two semifinals with eight riders in each.
Crain was already dealing with some pain after cracking her right humerus bone - the large bone in the upper arm - during a crash at the world championships in May. She has been doing rehab ever since, and proclaimed it good enough to compete in London.
"My expectations are obviously to get on that podium and get a medal," Crain said recently. "I've been on the podium before, and it's been against every girl out here."
Mike King, who runs the BMX program for USA Cycling, said he was confident that Crain would be able to compete for an Olympic medal despite being a late addition to the team.
"We have the utmost confidence in the depth and talent of our women's BMX program," King said. "Brooke has posted consistent international results, has been training hard and is fully prepared to step in and make an impact in London."
Martin was hurt during a crash on a course built in California to closely resemble the Olympic track. She was doing one last training ride by herself when a mechanical problem caused her to fall, the impact lacerating her liver and collapsing her right lung.
Martin was rushed to the hospital, but her teammates didn't know how badly she was hurt.
"With our sport, injuries like that happen all the time, and I knew being Arielle she wanted to come back in 24 hours if she could," said Crain, who witnessed the crash. "I just thought she'd get a couple of scrapes and bruises and be good to go."
Word finally filtered back from the hospital that Martin's injuries were life-threatening, and Crain knew as the first alternate that she would be riding at the Olympics.
Martin has already undergone three surgeries, the most recent earlier this week, when doctors put a stent in her liver to help alleviate abdominal pressure. Her family said in a statement that she is doing better, and that the long-term prognosis is good.
Crain is part of one of the top teams at the London Games.
The three-man U.S. team of Connor Fields, David Herman and Nic Long expects to build on a silver and bronze that Mike Day and Donny Robinson delivered when the sport made its debut in Beijing - King has said all along that the only result the team is interested in is gold.
Fields started well by posting the fourth-fastest seeding time of the 32 riders in the men's competition. Long was close behind in seventh, and Herman qualified in 15th.
"I feel pretty good," Fields said. "I definitely made a couple of mistakes and have some things to improve in the next couple of days, but I'm happy. It gives me the one seed in my heat tomorrow and I'll take the positives and move forward."
Assuming she is healthy, Crain joins Alise Post in giving the U.S. a pair of medal contenders in the women's event. Post had the eighth-fastest time during her seeding ride Wednesday.
"It wasn't my best run," Post said, "but I wanted to be in the top eight and that's where I am."
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