Marshall is from Arlington, Texas where she attended Seguin High School, competing in volleyball and track and field.

[2] Marshall's most notable prep victory was at the 2016 New Balance Indoor Nationals in New York, where she was the favorite heading in to the competition.

[5] The performance was advantaged by the 1,800 metres of elevation in Queretaro providing thinner air for sprinting, allowing for the second-place finisher Chanel Brissett to also break the old meeting record.

Despite dealing with a left hamstring injury, Marshall took an early lead in the Trials finals but finished 0.1 second outside of the top three required for selection to the 2021 U.S.

[8] Marshall achieved her first senior national medal at the 2023 USA Indoor Track and Field Championships, finishing 2nd in the 60 m hurdles behind only Alaysha Johnson.