The Professor's tenure at ESPN is coming to an end.

NFL insider John "The Professor" Clayton is leaving ESPN as part of the sweeping layoffs at the Worldwide Leader in Sports, sources tell Sporting News. ESPN and Clayton both declined SN's request for comment, but Clayton confirmed his status in a tweet Wednesday afternoon.

I guess you saw the news. After 23 years I won't be contributing to ESPN. Two words. Thank you. My bosses and co-workers are the best. — John Clayton (@ClaytonESPN) May 31, 2017

The well-respected Clayton has served as a senior NFL writer and commentator at ESPN for 23 years.

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Sporting an unforgettable ponytail, Clayton starred in one of the most memorable "This is SportsCenter" TV commercials of all time. In the 2012 commercial, Clayton delivers a report to anchor Stan Verrett. Once his on-air hit is over, the secret rock n' roller rips off his faux suit, lets down his mullet and cranks up the music.

"Hey Mom, I'm done with my segment," screams Clayton, while chowing down in his bed.

By the way I am keeping the ponytail — John Clayton (@ClaytonESPN) May 31, 2017

Clayton played the spot for laughs. But there's no joking about his Hall of Fame journalism career.

He started covering sports as a Pennsylvania high schooler. Clayton covered the Terry Bradshaw-Mean Joe Greene Steelers for the Pittsburgh Press in 1976.

That memorable team reached the AFC championship game before it lost to Ken Stabler and John Madden's eventual Super Bowl champion Raiders.

Clayton served as the Tacoma News Tribune's Seahawks beat writer from 1986 through 1998.

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In 2007, Clayton was inducted into the writer's wing of the Pro Football Hall of Fame.

Clayton is still talking NFL with an ESPN connection. He has his own weekday radio show on 710 ESPN KIRO Seattle. The AM sports radio station is not owned by ESPN, however. It's owned by Bonneville International and licenses the ESPN name.

I am well taken care of by ESPN. I have daily show on 710 ESPN Seattle 10 to 12 pacific. I fill in on Sirius on moving the chains. — John Clayton (@ClaytonESPN) May 31, 2017

Clayton is the latest big NFL name to emerge from the ESPN layoffs. Among the others:

— Trent Dilfer, former Super Bowl winning quarterback turned "Sunday NFL Countdown" analyst. Joined ESPN 2008.

— Ed Werder, NFL Insider. Joined 1998.

— Britt McHenry, Sunday NFL Countdown correspondent. Joined 2014.

— Ashley Fox, reporter/analyst for SportsCenter. Joined 2011.

— Paul Kuharsky, Titans beat writer for NFL Nation. Joined 2013.

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ESPN is not the only media outfit laying off seasoned, respected sports journalists.

I have been laid off from the FW Star-Telegram, my employer since 1999. Life sometimes throws you a curve. I just have to learn to hit it. — Charean Williams (@NFLCharean) May 16, 2017

After 26 years, I was laid off by the Fort Worth Star-Telegram today. Thanks to my great bosses and co-workers 4 the good times. God Bless. — Dwain Price (@DwainPrice) May 16, 2017

The Fort Worth Star Telegram laid off NFL writer Charean Williams and NBA writer Dwain Price.

Some welcome good news in the shrinking sports media industry: Williams, the past president of the Pro Football Writers of America, was just hired by Pro Football Talk.