Independent Olympic Athlete.
When he crossed the finish line, he touched those three letters, then pounded the left side of his chest with his fist in a subtle but significant gesture to describe his Olympic experience.
The south Sudan refugee competed Sunday under the banner of the International Olympic Committee. A runner without a country, he didn't want to compete for Sudan and couldn't compete for the United States, where he lives and trains but is not a citizen. He finished 47th, 11:31 minutes behind the winning time.
The time was of little consequence.
"Finishing the marathon is more important than anything like that," he said. "This is special for the people who support me, in the United States and the whole world and my people in south Sudan. It was important for me to finish, no matter what."
Not having a flag "doesn't worry me a lot because coming here, technically, I feel like I was representing south Sudan even though I was not wearing it," he told The Associated Press immediately after the marathon. "It is important to bring the name of south Sudan here and raise awareness of the issue going on in south Sudan."
Marial, 28, was born in what is now the newly independent country of South Sudan. He fled a long time before the south broke away from Sudan last year and doesn't have any South Sudanese documents. Although he is now a permanent resident in the U.S. — he trains in Flagstaff, Ariz., — he's not a citizen there, either.
He was offered the chance to represent Sudan at the games but declined.
With no passport, no country and seemingly no hope, Marial met fellow runner Brad Poore at a race in Minneapolis in October and 10 months later — with plenty of help from his new friend — he got to compete on the final day of the London Olympics.
Poore had phoned everyone he could think of from charities to senators, embassies and border agencies so that Marial would be able to compete.
Marial had run only two marathons previously, but finished both in Olympic qualifying times. His second was just two months ago in San Diego, leaving him very little time to taper for the biggest race of his life.
"It was a heavy responsibility on my shoulders, but it was great," he said. "I feel blessed to be able to do this. Two marathons back-to-back in two months, was not ideal. The whole thing is to do this to honour our people. Support the refugees and the people of South Sudan."
Thousands of people lined the marathon route, which wound past many of London's famous landmarks and finished in the Mall, within sight of Buckingham Palace. He saw people waving south Sudan flags, and yelling encouragement to him in his native tongue. And he heard plenty of other support from the fans who have followed his story.
For that, he was grateful to the IOC for helping get to London.
"The IOC is great. It's special. I can't thank them enough for giving me this opportunity," he said. "At the same time, It's about the people. In my heart here, I'm carrying those people in my heart."