Column: Track trials get out of the blocks with Allyson Felix

Merely getting to the starting line at the U.S. Olympic track and field trials has proved to be an insurmountable challenge for several athletes with Olympic experience. Others who have hobbled their way to the 10-day event that will determine the U.S. squad for the Rio de Janeiro Summer Games will test their fitness and their will when competition begins Friday, with finals in the men’s shotput and men’s 10,000-meter race highlighting the program at Hayward Field.

The top three in each event will go to Rio, provided they’ve met the Olympic qualifying standards.

The first round of the women’s 400 on Friday will be the first of many suspenseful moments in the trials. Los Angeles-based Allyson Felix, who won gold in the 200 at London four years ago as well as two relay gold medals, has been preparing for a difficult 200-400 double, but she injured her ankle in a weight-room mishap in April. This will be her first real test of her ankle, because she hasn’t competed in any major races this season.

“It’s this huge thing you have to get through. A lot of times you do feel like it’s this bigger thing than even the Olympic Games,” she said of the trials. “A lot of other people from other countries, they don’t have that pressure that you have to go through here. It’s the hardest team to make and everything has to click on that specific day.”

Only two women — Valerie Brisco-Hooks of the U.S. in 1984, and Marie-Jose Perec of France in 1996 — have won the 200 and 400 in the same Games. The only man to have won that golden double is Michael Johnson of the U.S.

Also worth watching Friday in the women’s 400 is the 2012 Olympic champion, Sanya Richards-Ross, who has said this will be her last competitive season. She had foot surgery late last year and has been hobbled by a hamstring injury.

Carmelita Jeter of Gardena, who won gold (relay), silver (100) and bronze (200) in 2012, won’t make an Olympic return. She withdrew from the trials Thursday after aggravating a quadriceps muscle injury. “You guys know this has been a rough two years for me,” she said on Instagram. “Don’t you ever forget — I’m still the fastest woman alive.”

Nick Symmonds, a six-time U.S. champion in the men’s 800 and the fifth-place finisher in London, also took to social media to announce his withdrawal from the 800. He posted a photo of his left ankle and said he couldn’t compete because of a torn ligament and a stress fracture.

Also out is two-time Olympic hurdler Lolo Jones, who competed in the 2014 Sochi Winter Games in bobsled but has been slowed by hip surgery. She said Thursday she’s not retiring but added, “I don’t know what my future holds besides the fact that I’m about to go to the store and get some donuts.”

The absence of some familiar faces could ease the way for some relative newcomers to make an impression during the trials and perhaps beef up the U.S. medal totals at Rio. The 2012 track and field squad won 29 medals, its best showing since a 30-medal haul in 1992. The men won three gold medals among their 15; the women won six gold medals and 14 overall.

Qualifying will start Friday for the women’s high jump, with 18-year-old Vashti Cunningham expected to be a top contender. The daughter of former NFL quarterback Randall Cunningham, she won the U.S. indoor title with a jump of 6 feet, 6 ¼ inches, a world junior record. She also won the world indoor championship by clearing 6-5. “I’m excited for this to be my first trials and I’m looking forward to competing for America again for something as big as the Olympics,” she said at a news conference Thursday.

The 100-meter hurdles could be a showcase for 23-year-old Keni Harrison, who in May ran the second-fastest time ever recorded by a woman, 12.24 seconds. She has the top four times in the world this season. “Of course, I’ve thought about breaking the world record,” Harrison said, referring to the 12.21 by Yordanka Donkova of Bulgaria in 1988. “Each race I just like to execute and just come across the line first. I think the times will come.”

The men’s 10,000 on Friday will feature Oregon alumnus and 2012 Olympic silver medalist Galen Rupp, who earned a Rio marathon berth by winning the marathon trials in Los Angeles in February. It’s unclear whether he would attempt a 10,000-marathon double if he finishes in the top three here.

It should be clear Friday whether Felix, 30, will be able to pursue her rare double. “Only by the grace of God I will walk to the starting line [Friday],” she said on Instagram. “Undoubtedly, this will be the hardest team I try to make. I refuse to give up on my dreams. I’m a fighter and [Friday] one of my biggest fights begins.”

helene.elliott@latimes.com

Twitter: @helenenothelen