Te 62-year-old said the publication of a one-minute, 41-second excerpt of a video of him having consensual sex with the wife of his then-best friend, radio shock jock Bubba the Love Sponge, roiled his personal and professional life.
"I was completely humiliated," he said, noting the embarrassment was personal and professional. "It was even embarrassing as my character. Hulk Hogan was embarrassed."
Hogan is suing Gawker for $US100 million ($NZ147 million) in damages over the leak.
Going in court by his legal name, Terry Bollea, he described his modest upbringing and start in wrestling, for a time living out of his car before becoming famous.
The wrestler, wearing a signature bandana with a black suit and a cross necklace, called the Hogan character "completely opposite" to his true personality, which he described as soft-spoken and non-argumentative.
Lawyers for the longtime champion of World Wrestling Entertainment and reality TV star say he had a right to expect privacy in a private bedroom and the video was filmed without his knowledge.
Gawker's editors were motivated by power and brand promotion when they posted the clip, an attorney for the wrestler told jurors during opening statements. Gawker attorneys also tried to raise doubt about whether the wrestler knew about the filming.
Gawker sees its 2012 post as protected speech under the First Amendment of the US Constitution, and contends it was reporting on a celebrity who publicly discussed his sex life.
Gawker's founder Nick Denton sat in the front row on the first day of a civil trial in St. Petersburg, located in the county where Hogan lives, along with a former editor involved, A.J. Daulerio.
"Gawker believes this kind of reporting is important," an attorney for the company, Mike Berry told jurors, explaining that celebrity sex tapes are among the "uncomfortable" topics important to the outlet, known for gossip and media reporting.
A loss could put Gawker out of business, though the website will appeal an unfavorable verdict, another attorney for the company said.
The wrestler said the incident occurred at a personal low-point as his marriage was ending. He said the recording happened in a place where he had let down his guard.
"It was the only place where I felt safe, crazy as that sounds," he said of his friend's house, where the video was taped.
