The 17-year-old ran a season best time of 8.51 seconds in the 60m event at the World Indoor Athletics Champs in Portland, Oregon, at the weekend, just one hundredth of a second off her personal best time.
She was born and raised in Minnesota, in the United States, but said it was a blessing and privilege to represent the country in which her father, 2008 Olympian Roman Cress, was born.
Mariana Cress said she plans to spend the next few months working toward her goal of qualifying for the Rio Olympics.
"Just extra hard training. School always comes first so it's going to be hard balancing both. I'm just going to work hard and pray that the Marshall Islands confirms me to get sent to Rio," she said.
"I think I'm one of the only females that's really running out there (from the Marshall Islands) but someone might come up – you never know. Stuff happens so I'm just praying that I stay in that spot to go to Rio."
Cress said the Marshall Islands is expected to send one male and one female athlete to the Summer Olympic Games later this year.
(Roman Cress and daughter Mariana Cress during the 2014 8th Micro Games in Pohnpei. Picture: Fox Sports Pulse)