John was one of the country's foremost NFL Insiders who covered the league to great depths during a 20-plus-year career at ESPN.
He died at 67.
The team said in a statement that they were "heartbroken to learn of the passing of John Clayton after a battle with a brief illness at the age of 67."
Nicknamed "The Professor", he was known for reporting on the NFL in such a detailed manner that anyone paying attention walked away a little more educated.
He did that for 50 years, starting in 1972 when he was a reporter for the Pittsburgh Steelers, and ending just a few weeks ago when he broke down the blockbuster trade of Russell Wilson to the Denver Broncos.
The Professional Football Writers of America gives the Bill Nunn Memorial Award annually for long and distinguished reporting on football.
He said at the time that it was the highest honor any writer could receive.
As a jack-of-all-trades for its NFL coverage, ESPN hiredClayton in 1995. SportsCenter producers created a weekly segment called " Four Downs", which pits former quarterback and analyst Sean Salisbury against Clayton. It was a must-see TV.
As did his appearances on "This is SportsCenter" commercials for Disney, which to this day are hailed as among the best, including a spot where he appeared for a TV hit in a tie, let down his long hair and began rocking out.
While in high school, he covered the Steelers and then attended Duquesne. He was hired by the Pittsburgh Press during his senior year and later moved west to cover the Seattle Seahawks for the Tacoma News Tribune before he was hired by the sports network.
He hosted The John Clayton Weekends show on Seattle Sports 710. He was a sideline reporter for five seasons.
He loved football until this day.
He told the Pittsburgh Post Gazette how long he would keep covering the NFL. The salary information, which we didn't have access to years ago, is now available, as is the coaches tape. There is so much information and analytical stuff.