EUGENE, Ore. -- Track officials denied an appeal by 800-meter Olympic champion Athing Mu, who got tangled in a pack of runners and fell at the U.S. trials, denying her a chance to defend her title.

Coach Bobby Kersee said Mu got clipped by another runner on the backstretch of the first lap, which caused her to veer to her left and tumble to the ground.

USA Track and Field officials reviewed footage of Monday night's race deep into the evening but eventually denied the appeal. They did not give details. Normally, protests are granted when there's clear evidence of a runner obstructing another runner. Incidental contact is considered part of normal racing.

Mu, who scrambled to her feet to complete the race, will be eligible for the relay pool. She was part of the gold medal team in the 4x400-meter relay at the Tokyo Games.

Kersee said Mu, 22, got spiked, suffered scrapes from the fall and hurt her ankle.

He acknowledged the unforgiving nature of the U.S. system, which awards spots in the Olympics to the top three finishers at the trials but does not make exceptions for past performances or Olympic champions.

"I've coached it, I've preached it, I've watched it," Kersee said. "And here's another indication that regardless of how good we are, we can leave some better athletes home than other countries have. It's part of our American way."