US endurance swimmer Diana Nyad's team says she made it through her first night in the Straits of Florida with almost no sightings of poisonous jellyfish.
A post on Ms Nyad's blog says she is doing well and the crew is upbeat, though she expressed some fatigue during a pause to eat. Doctors examine her regularly and say "she's looking very good".
The 64-year-old is trying to become the first person to swim from Cuba to Florida without a shark cage.
It's Ms Nyad's fourth attempt at the feat in the last three years. She also made an unsuccessful try with a cage in 1978.
If she is successful this time, she expects to take about 80 hours to reach the Florida Keys.