RIO DE JANEIRO — The adjectives could be viewed one of two ways. The other runners called the performance “absurd,” “crazy” and “unbelievable.” Almaz Ayana’s Olympic debut was all of those things.

Competing in the 10,000-meter race for only the second time, the Ethiopian shattered a world record that stood for nearly 23 years by more than 14 seconds.

The first medal event of the track and field competition set the stage for the conflicted emotions sure to follow over the next nine days. This is a sport where greatness and suspicion are joined, and Ayana’s incredible feat Friday was immediately both applauded and questioned.

The 24-year-old moved around the track like a machine, maintaining a blistering pace and racing in a gear the running world had never seen. She finished in 29 minutes, 17.45 seconds, a full 15 seconds ahead of Cheruiyot Vivian Jepkemoi from Kenya, a rub-your-eyes time that’s ripe for celebration and skepticism.

“I do not really believe that she is 100 percent,” said a Swedish runner, Sarah Lahti, who finished 12th. “It is too easy for her. … I cannot say that she is not clean, but there is little doubt.”

Ayana, who competed in the 3,000-meter steeplechase before recently embarking on longer distances, defended her run and insisted she was clean.

“My doping is my training,” she said through an interpreter. “My doping is Jesus. Otherwise I’m crystal-clear.”

The United States’ best hope in the race was 31-year-old Molly Huddle. She came to Rio thinking a time of 30:20 would be good enough for the medals podium. Huddle finished in 30:13.17 and set an American record. That time would have easily won gold four years ago in London. On Friday, it was good only for sixth.

“These places might be a bit mobile,” she said of the top finishers. “Who knows? That’s a very, very fast time.”

Finishing ahead of Huddle were two Ethiopians and three Kenyans, from countries that have competed under a doping cloud this season.

An Ethiopian coach of a world champion was arrested two months ago in Spain after investigators found 60 syringes of EPO and other banned substances in his hotel. Several runners have been suspended or investigated this year for doping. The country’s Olympic committee has drawn the ire of World Anti-Doping Agency for its lax testing and been told by the International Association of Athletics Federation, track’s governing body, they face a possible ban if they don’t get better.

It was under that backdrop that Ayana won Friday. She called it “a dream come true.”

“I have worked very hard,” she said. “I wouldn’t say that my recent training has been any different from before, but it was hard and it was all worth it.”

An early-morning rain and cool temperatures meant conditions were favorable, but after the race some runners needed time to process Ayana’s blazing time.

Huddle said she was proud to break the U.S. record and excited about her time, but wasn’t exactly celebrating. Asked if she questioned the validity of the top times, Huddle said, “Not in the race, I didn’t. I can’t think about that during the race. That is a very fast time. We’ll just see”

American Emily Infield, competing in her first Olympics, ran a personal-best 31:26.94, which was only good enough for 11th. She was impressed with Ayana’s time but careful with her words.

“It’s absurd,” she said. Asked if she felt the winning time was legit and the top runners clean, she said, “I shouldn’t comment. I don’t know.”

Ayana has a shot at a second gold medal. She’s also in the 5,000-meter race next week.