The sailfish began charging at the boat, then jumped out of the water and stabbed the woman in the groin as she stood next to the boat’s center console, according to the Martin County Sheriff’s Office .
It happened so fast the woman didn’t have time to react, she told an officer who responded.
The two men on the boat immediately applied pressure to the wound, according to an incident report filed last week.
The woman, identified as Katherine Perkins, was in good condition at the hospital Sunday, a spokesperson for HCA Florida Lawnwood Hospital told CNN.
The ship was about two miles off the coast of St. Lucie when the incident took place.
Sailfish have long beaks, similar to those of marlins and swordfish. They are considered by many to be the fastest fish in the ocean, according to the Ocean Conservancy.
The sailfish was estimated to weigh 100 pounds, according to the sheriff’s office report.
CNN’s Michelle Watson and Theresa Waldrop contributed to this report.