American superstar Lexi Thompson once crowned Keeley Marx as her “biggest fan in Australia” but now the pair will share the stage at this week’s US Women’s Open in Pennsylvania.

Marx’s rise from self-confessed “fangirl” to the richest tournament in women’s golf has been a rapid one, if not slightly unexpected.

The 20-year-old Victorian recently completed her freshman year at Iowa State University but will now graduate to the big time in professional golf as one of six Aussies teeing it up at Lancaster Country Club.

The daughter of Australian representatives in discus and javelin, Darren and Rochelle Marx, Marx grew up playing amateur golf against the likes of Stephanie Kyriacou, Gabriela Ruffels and Grace Kim.

She now steps into the arena occupied by her childhood hero… and the serendipity of the moment is not lost on her.

“I’m the biggest Lexi Thompson fan,” said Marx, who will take a break from summer classes at Iowa State to play her first major.

“When I was younger, if Lexi was doing it, I wanted to do it. I’ve met her a couple times when she was playing tournaments. I’d go watch her and she’d sign a glove for me.

“I feel like if I get to see her, I’m going to go up to her and be the biggest dork and go say hi. I’m a fan girl for sure.”

Thompson won’t be the only familiar face for Marx at Lancaster Country Club.

Now one of the LPGA Tour’s lead commentators, Morgan Pressel – like Thompson – qualified for her first US Women’s Open at just 12 years of age but.

Now, 23 years later, she will be a keen observer of Marx’s major debut from the NBC commentary booth.

“I got a message from Morgan, so that was also pretty exciting,” said Marx, who also received a congratulatory message from Aussie legend Karrie Webb after topping the US Women’s Open qualifier in Chicago.

“I followed her to a couple of tournaments when I was younger and she started following me on Instagram.

“She’s going to be commentating there so I’m like, Wow, this is full 360. I watched when you played and now you’re going to be commentating when I’m playing.”

A member at The Heritage Golf and Country Club in Melbourne’s north-east, Marx represented Australia at the Women's Amateur Asia-Pacific Championship 14 months ago before embarking on her first year at Iowa State.

It was only that there was a small window in this year's college golf schedule that prompted Marx to pack her Ford Escape named ‘Jimmy’, enlist Iowa State teammate Liyana Durisic as caddie/co-driver and embark on the six-hour trip from Iowa to the US Women’s Open qualifier at Briarwood Country Club.

“It was more of a whim, not going to lie,” said Marx, who finished 13th at the NCAA Division 1 Bryan Regional in Texas the week prior.

“It was literally the only qualifier that would fit the college schedule so drove up there and I was like, Wow, OK, we got to do this.”

One off the lead after Round 1 of the 36-hole qualifier, Marx was on her third-to-last hole when rain forced the suspension of play.

It was only then that she was made aware that a spot at the US Women’s Open was in her grasp.

“This guy is picking us up in the buggy and he’s like, ‘The leader is at 1-under, is that any of you guys?’” Marx recalled.

“And I’m thinking to myself, I’m 2-under; oh boy.

“We get off the buggy and I say to my teammate, ‘I’m really going to have to hold myself together for the last couple holes.’”

She held it together long enough to take medallist honours, gifting herself an early insight into what life as a professional golfer may look like.

“This is really going to give me a great pathway into what I might want to choose to do,” said Marx, who is majoring in journalism.

“Obviously I have a couple more years of college so, at the moment, dreams are that I go play pro golf on the LPGA, but things change.

“It definitely is a great stepping stone into hopefully what I do.

“To play my first major, it’s really going to just show me what I can hopefully do in the future.”