Distance swimmer Diana Nyad is attempting a 103-mile swim from Cuba to Key West. She entered the water Sunday around 7:45 p.m. ET, from Havana’s Hemingway Marina. On Monday afternoon  she more than 20 miles off Cuba andstruggling with shoulder pain and asthma but continuing to swim strongly, CNN’s Matt Sloane reported.

Nyad ‘doing great’ on swim

CNN is the only network accompanying Nyad on her swim, which could take 60 hours or longer.  Producer Matt Sloane is leading a CNN team traveling on  one of Nyad’s chase boats. They are carrying a SPOT GPS tracker, which transmits the group’s position via satellite.

Gallery: Diana jumps in

Sloane will be Tweeting throughout the swim, and he’ll appear live on CNN from time to time to update viewers on the 61-year-old swimmer’s progress. Nyad’s team also will be Tweeting and blogging.