She previously played with the United States women's national under-19 basketball team and the University of Notre Dame.

[2] She has played internationally in Latvia (TTT Riga),[3] Israel (Bnot Hertzeliya),[4] Australia (Perth Lynx),[5] Italy (PF Schio),[6] and Turkey (Çukurova Basketbol).

Fierce basketball competition became a part of family life in the Mabrey household with Marina frequently competing with her older brother and sister in their driveway and local park.

The team executed the largest comeback in a championship game in NCAA women's basketball history, overcoming a 15-point deficit to achieve a 61–58 victory over fellow No.

[19] Prior to the 2020 WNBA season, Mabrey was traded by the Sparks to the Dallas Wings for a 2021 second round draft choice.

[22] In her first game[23] she scored 24 points and led her team with eight rebounds to win 89–81 over defending champions UMMC Ekaterinburg which contained WNBA players Brittney Griner, Courtney Vandersloot and Emma Meesseman.

[31] Following this game, she was unavailable for over a month due to a foot injury[32][33] but returned to contribute to the Lynx ending the season as runners-up in the WBNL to Melbourne Boomers after losing the final series by two matches to one.

She followed this up two weeks later with seventeen point performance and vital bucket and interception in the last seconds to win a bronze medal with PF Schio for third place in the 2022–23 EuroLeague Women finals in Prague.

[37] On August 17, 2024, it was announced that Mabrey would appear and play in the inaugural season of Unrivaled, a new women's 3x3 basketball league founded by Napheesa Collier and Breanna Stewart.

In pre-season training, Mabrey sustained a right calf injury requiring a minimum of 2-weeks rest and her missing the start of the 2025 season.

[39] Stats current through end of 2024 season In 2019, Mabrey started her own shirts called This Is My Kitchen in reference to sexism in sports and her 2018 NCAA Women's Basketball Championship win which she sold online for a limited time.