Yusra Mardini, a member of the Refugee Olympic Team, clocked in at 1:09:21, just off her entry time of 1:08:51. But despite winning her heat, the 18-year-old did not qualify for the semifinals. Her time put her in 41st place overall and only the top 16 swimmers moved on to the semifinal round.
But Mardini will have another chance to advance to the medal round, when she swims the women’s 100-meter freestyle event on Wednesday.
About two years ago, Mardini was swimming to save her life and others. She was one of 20 refugees crossing the Mediterranean Sea in a boat when the motor stopped running.
"It was quite hard to think that you are a swimmer and you might end up dying in the water," Mardini said in an article on the Rio Olympics website.
Mardini fled the Syrian war in 2014 with her sister, who was with her on the boat. They dived into the water with one other passenger and pushed the boat to the shore. Everyone on board was saved. Mardini lives in Berlin, where she trains at Wasserfreunde Spandau 04.
ABC News' Drew Millhon contributed to this story.