Caslick is part of the Australian women's rugby team, which beat New Zealand this week to win gold at the Olympic debut of rugby sevens.
"It's pretty special. It hasn't really sunk in," Caslick said. "I'm sure in 20 years we'll look back on (this moment) and see how what we did changed women's sport."
But making the Olympics, or winning a gold medal, wasn't something she could have even dreamed about as a little girl.
"When I was growing up, it wasn't really an option," said Caslick, 21. "We looked at boys and thought that's awesome that they can play sports professionally, I'd love to do that. But (I) never thought it would be a possibility."
She says she didn't grow up thinking she wanted to be a rugby player. She used to play touch football because her brothers played it.
But after a touch football tournament she got a letter from the Australian Rugby Union, and that was the start of a career that has now seen her compete at the Rio Games.
With women like her becoming professional athletes and winning medals, what advice does she have to younger women aspiring to become rugby players?
"Just not to be scared and afraid of it, because it's so much fun. It does get easier once you give it a go."
"I was scared at the start," she said, "You've got to be confident."