The man, only identified by the show as David, simply nodded when appraiser Peter Planes told him the model was a lot like one worn by the late actor Paul Newman, which typically auctions for around $200,000.
David then lost his footing in what appeared to be a pratfall after Planes noted that the word "Oyster" inscribed on the watch is “extremely, extremely rare,” putting it more in the $400,000 range.
“You OK?” Planes asked David who jumped back up to laughter. “Don’t fall. I’m not done yet.”
Planes said since the watch is in nearly perfect condition, it could appraise for between $500,000 to $700,000.
“Half a million dollars, $700,000 — that’s life-changing for somebody,” Planes told The Washington Post.
David said he bought the watch while stationed in Thailand. He ordered it from the base exchange for a 10 percent discount. He was going to use it to scuba dive.
“I looked at it, and I said, ‘You know, this is really too nice to take down in the salty water,’” David said, adding that he had only worn it two or three times.
The inscription on the Oyster Cosmograph, also called a Daytona, usually wears off the watches quickly, Planes, a watch expert, said, which is what makes it so special, the Post reported. The word Oyster, according to Planes, means the watch is particularly water-resistant.
Newman's actual Daytona Rolex went for a record-setting $17,752,500 in 2017, the Post reported.
Planes said he didn’t ask what David planned to do with the money he could earn from selling the timepiece.
“He’s saved it all these years,” he said, according to the Post. “He may be saving it more."
The "Antiques Roadshow" episode with the mesmerizing discovery aired Sunday.