They were submerged in the murky water, ascending slowly as required for deep cave dives.
About halfway toward the entrance point, Gregory Snowden noticed his friend was struggling with his breathing apparatus.
Sgt. Donna Black, a spokeswoman with the Hernando County Sheriff's Office, described what happened next.
The divers had been more than 270 feet below the surface and were 500 feet upstream from their destination, so time was critical for James Woodall to get his breathing gear working properly.
During his struggle, Woodall pushed his friend into a pile of sand, which covered his mask.
By the time Snowden regained his sight of Woodall, it was too late, Black said.
"He realized he was lifeless and could not resuscitate him," she said.
The two traveled from Madison County, Ky., to Eagle's Nest Underwater Caverns in the Chassohowitzka Wildlife Management Area. The site, also known as Lost Sink, is a popular destination for local and out-of-town cave divers, according to employees at several local diving shops.
Snowden reached the surface shortly after 6 p.m. and called 911. Recovery divers were called from St. Petersburg and Citrus County, according to the sheriff's office.
By that time, both men were underwater for approximately four-and-a-half hours, Black said.
The body was recovered shortly after midnight, according to a media release.
Woodall, along with Snowden, was certified through the Professional Association of Diving Instructors, according to New Horizons Diving Center in Lexington, Ky., where both men are members.
Neither was certified in cave diving, Black said.
Multiple calls to both men's homes in Lexington were not answered.
"Our entire shop is doing all we can for the family," said Matthew Skaggs, manager of New Horizons. "That's all we're focused on right now."
Skaggs said he could not say whether Woodall or Snowden had any certifications in cave diving, but according to the shop's Web site, the two had been on similar dives prior to their trip to Eagle's Nest.
Walter Pickel is a certified cave diver out of Tampa. He said he spoke with some of the divers who searched and recovered the body.
He owns a similar type of life-support system both men used for their dives.
It is known as a rebreather. It recycles exhaled gas and allows the diver to be submerged for an extended amount of time. It is a device commonly used by Navy SEAL teams.
Pickel said he has never used it for a deep cave dive. To do so would break the number one rule known by mostly all cave divers - if you're not trained for it, don't do it.
"I have a rebreather, but I'm not certified with it so I don't use it," he said. "I promised my wife I wouldn't, so I don't."
Jeff Petersen is another local cave diver. He estimated he has had upward of 30 dives at Eagle's Nest.
"To even get a rebreather, you have to go through some pretty elaborate training," Petersen said. "It's a very involved process. You need to be vigilant on what your equipment is doing while you're concentrating on where you are.
"If you put a rebreather diver in there without a cave certification," he continued, "that's the same as a death warrant."
Both Petersen and Pickel were reluctant to guess what led to Woodall's fatal accident because it might have resulted from a number of factors. For starters, if the mixture of gases contains too much oxygen, the results can be toxic and cause the diver to convulse.
Oftentimes during a seizure, the diver spits out the mouthpiece and loses consciousness. If someone nearby doesn't jam the regulator back into the diver's mouth, he or she could drown quickly, Petersen said.
Pickel said he constantly hears stories about people who continuously go on cave dives in spite of not ever pursuing the necessary certifications.
"They will say something like, 'I've been doing this for so long, I don't need to be cave trained,'" he said. "That's just a horrible attitude. Those people might as well say, 'I'm going to go ahead and die soon.'"
Six divers have died at Eagle's Nest since 1981. The previous fatal accident was in June 2004 when two local divers drowned while being stuck in the caves, according to news reports.