Olivia Mehaffey won all three of her matchplay encounters as the Arizona State University went on to beat Northwestern 3.5-1.5 in the final to capture the NCAA Division One title at Rich Harvest Farms.
The Royal County Down Ladies' star was a 5 and 4 winner in the quarter-finals and a 2 and 1 winner in the semi-finals before demolishing Sara Cho 4 and 3 in the final.
The win was ASU's eighth team title, the most of any women's golf programme in NCAA history.
Winners in 2009 after a dominant period that yielded six wins in nine years (1990, 1993, 1994, 1995, 1997, 1998) the win looked unlikely before the team rallied at the death to beat Stanford 3-2 in the semi-finals with two wins on the 19th.
In the final, Mehaffey raced five up after six and eventually closed out the match on the 15th before teammates Roberta Liti and Linnea Strom added the title-clinching wins and NCAA Individual winner Monica Vaughn won the 18th to halve with Hannah Kim.
Kacie Komoto got Northwestern's lone win with a 3 and 1 victory over Sophia Zeeb.
Writing on Facebook, Mehaffey said: "SUN DEVILS ARE NATIONALS CHAMPIONS... I don't even know what to say but wow!! I feel so lucky to have a fam like you guys and I love you! I'm so happy to be part of the sundevil family and get to compete for my dream school.
"Today has been one of the best days of my life and I'm so proud to see our dream of winning a national championship come true this week.. hard work pays off!
"Special shout out to our men's team for their support today.. you guys rock! Now let's get another trophy back to Tempe 😈❤ @ Rich Harvest Farms."
"We're all floating on cloud nine," said head coach Missy Farr-Kaye. "We keep saying, is this real, is this real, and it is. This is a gruelling championship now with this format, and it's an exciting format, but you have to be ready to play a lot of golf.
The epic semi-final win over Stanford, which was not finished until Wednesday morning, was the key to ASU's triumph
Vaughn and sophomore Linnea Strom mounted the comeback as the Sun Devils found themselves down to Stanford, 2-1 in the semifinals, which had been suspended late on Tuesday night due to darkness following a rain delay.
Strom just going back to all square before the hiatus, while Vaughn was down one, both would make remarkable comebacks on the 19th hole to swing the momentum back in the Sun Devils' who won 3-2 to make the final
Semifinals – ASU beat Stanford 3-2-0
Olivia Mehaffey def. Andrea Lee, 2&1
Monica Vaughn def. Albane Valenzuela, 1UP in 19
Casey Danielson def. Sophia Zeeb, 3&2
Shannon Aubert def. Roberta Liti, 4&3
Linnea Strom def. Madeline Chou, 1UP in 19
Championship – ASU beat Northwestern 3-1-1
Olivia Mehaffey def. Sarah Cho, 4&3
Hannah Kim vs. M Vaughn, all square through 18
Kacie Komoto def. S Zeeb, 3&1
Roberta Liti def. Janet Mao, 5&4
Linnea Strom def. Stephanie Lau, 5&3