Gigi Hadid may be the "It" girl of the modeling world, but according to Tommy Hilfiger, there was a time when she wasn't allowed to show any skin during a runway show.

While speaking with Yahoo! Style, the legendary fashion designer revealed the real reason why he and his team dressed Hadid in an oversized poncho during his Fall 2015 New York Fashion Week show last February.

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"Our casting director said, 'She doesn't really fit because, you know, she's not quite as tall as the other girls, she's not quite as thin," Hilfiger explained. "So they put a red, white and blue poncho on her -- it covered a lot of her body unfortunately, but it received millions of hits."

"So I said, you know, why don't we ask her to design a line with us," he continued. "So I said, 'Gigi, come design this with me, we'll do a Gigi x Tommy couture line.'"

Now, Hilfiger couldn't be more proud of the 21-year-old California native for breaking down those beauty standards. Not only did he let her flaunt her petite figure in his Spring 2016 show a few months later, but he also kept his promise. Hilfiger collaborated with Hadid -- whom he calls an "All-American girl next door with an exotic twist to her look" -- on an adorably chic nautical collection that made its debut at New York Fashion Week in September.

To show off their Tommy X Gigi collection, the two put on a carnival-themed fashion show. ET was backstage with Hilfiger moments before the models rocked the runway, where he simply couldn't contain his excitement over the partnership.

WATCH: Tommy Hilfiger Gushes Over NYFW Collaboration With Gigi Hadid

"I can't wait to see all the models in the Gigi collection because these are girls Gigi cast for us, the clothes she designed for us and with us, and we've been working on them for almost a year," he gushed.