Kacy Catanzaro
Kacy Catanzaro on "American Ninja Warrior." NBC

Practically no one believed Kacy Catanzaro when she said she would complete NBC’s “American Ninja Warrior.” The five-foot gymnast weighs just 100 pounds, but on Monday she became the first woman to qualify for the final round of the NBC's competition.

The petite New Jersey native did more than just finish: she destroyed the course. The Townson University alum used every inch of her body to make her way through the competition, even leaping at times when she wasn’t tall enough to make it to the next obstacle. She made it look effortless as she glided through the course.

People in the audience, along with the hosts of the show, stared at her in awe; many chanted her name. She even stopped in the middle of the course to tell the audience she loved them.

Us Weekly noted that Olympians and Army men have failed to complete the course.

Twitter users were in awe of her athletic prowess and started the hashtag trend #MightyKacy.

Her coach, Brent Steffensen, was stunned by her accomplishment. "That was crazy!" he said afterward, according to Us Weekly. "What was that?"

"I've seen greatness during my NFL career," “ANW” host and former Oakland Raiders defensive end Akbar Gbaja-Biamila gushed to the news site. "And I've been in awe of people. But I am really in awe of Kacy."

Co-host Matt Iseman added: "We are seeing one of the greatest competitors, man or woman, we have ever seen inAmerican Ninja Warrior.’"

The former NCAA Southeast Regional Gymnast of the Year will now move on to compete in Las Vegas.

Check out the amazing video of Kacy Catanzaro below:

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