John Saunders, for three decades one of ESPN’s most versatile and well-liked on-air personalities, has died at age 61, the network announced Wednesday.

It did not reveal a cause of death. Saunders was not known to be suffering from any serious health problems and just last Friday had appeared at the National Association of Black Journalists convention in Washington, D.C.

Saunders had filled a wide variety of hosting and play-by-play roles since joining ESPN in 1986, notably succeeding Dick Schaap as host of the Sunday morning show “The Sports Reporters” in 2001.

One of his passions was serving as a founding member of the board of directors of The V Foundation for Cancer Research, named for the late college basketball analyst Jimmy Valvano, with whom he was close.

Co-workers of Saunders, who was hugely popular within the company as both a colleague and mentor, reacted with shock and dismay on television and in social media, where his name quickly skyrocketed to the top of Twitter’s national trending list.

“John Saunders represented everything that was good in a human being,” college basketball analyst Dick Vitale said in a statement. “He was all about family and helping people. He was as good as it gets, and he had deep loyalty and love for others.

advertisement | advertise on newsday

“His work with The V Foundation was so special. He loved Jimmy V and poured his heart and soul into the cause. He was always willing to share and give and he played a vital role in the success of helping so many.

“I can’t believe this stunning and horrible news. He will be forever in our thoughts.”

NFL reporter and analyst Chris Mortensen, who is on leave as he is treated for throat cancer, wrote on Twitter, “The news of John Saunders’ death could not be more crushing. We all loved him dearly. We grieve. We will miss him. Can’t replace the man.”

Added Jemele Hill, co-host of the ESPN show “His & Hers,” “John Saunders was a better person than a host, which is saying something. Classy. Professional. I can’t even describe his impact on me.”

A native of Ontario, Canada, Saunders had a particular affinity for hockey, and played the sport as a defenseman at the collegiate level. His brother, Bernie, played for the Quebec Nordiques of the National Hockey League from 1979-81.

@NewsdaySports

Saunders hosted ABC’s Saturday studio coverage of college football and select editions of ESPN’s College Football Live and ESPN’s college basketball studio coverage.

In recent years, he also co-hosted NFL highlight segments on Sunday night editions of “SportsCenter” during the football season. He anchored studio coverage from the College Football Playoff National Championship and hosted the postgame trophy presentation.

He is survived by his wife, Wanda, and daughters Aleah and Jenna.

NBC posted a video tribute from Mike Tirico, who recently joined that network from ESPN, in which he said Saunders “will be remember as a true pro, in every sense of the word . . . John was a great man, and we’ll miss him terribly.”

Said ESPN president John Skipper: “John was an extraordinary talent and his friendly, informative style has been a warm welcome to sports fans for decades.

advertisement | advertise on newsday

“His wide range of accomplishments across numerous sports and championship events is among the most impressive this industry has ever seen. More importantly, John was a beloved and devoted family man who cared deeply about people and causes, as evidenced by his long-standing efforts as a passionate board member for The V Foundation for Cancer Research.

“He was one of the most significant and influential members of the ESPN family, as a colleague and mentor, and he will be sorely missed. Our thoughts are with his loved ones at this extremely difficult time.”