Dick Ebersol, at the announcement of Versus’ deal with the NHL. (Richard Drew / AP)

Dick Ebersol, one of the most powerful and enduring figures in sports television for decades, is resigning from NBC Sports.

Ebersol, who has run NBC Sports since 1989 and oversaw coverage of eight Olympics, said he and the network could not reach agreement on a new contract. The news was first reported by The New York Times.

“It comes as a complete surprise,” Richard Carrion, the International Olympic Committee executive board member who negotiates U.S. rights, told the Associated Press. He added that he had been assured NBC is “100 percent committed to the Olympics and the rights process.”

Speculation about the decision by Ebersol, who led NBC to dominance in Olympic coverage and reshaped the content for prime-time viewers, centers on Comcast, the new owner of NBC Universal. There have been reports that friction existed between him and Comcast over his role in the new company and Comcast’s monetary commitment to retaining the rights to televise the Games.

The move brings uncertainty to the future of NBC as the home of the Olympics. The network has broadcast the Summer Olympics since 1988 and the Winter Games since 2002. Ebersol said he will not attend negotiations next month for the 2014 Sochi Games and the 2016 Rio de Janeiro Games. ESPN and Fox are expected made bids to cover the games.

Mark Lazarus, president of the NBC Sports Cable Group, will replace Ebersol.

Ebersol, 63, was named the head of the NBC Sports Group, which includes NBC Sports, Versus, the Golf Channel and the regional Comcast sports networks, earlier this year. His first move was getting rights to the NHL for Versus for $1.9 billion over 10 years in April.

“What I have enjoyed most is working so closely with so many truly outstanding and incredibly talented people over decades of producing some of the greatest events in the world,” Ebersol said in a statement released by NBC. “Those relationships are what I cherish most. I have always said this business is about relationships and I have been fortunate enough to have more deep and meaningful friendships than any man could imagine.

“It has been a sincere privilege to tell so many remarkable stories that have inspired me throughout my entire career. Some of my favorite memories come from reading letters and talking to viewers who also have been moved by such powerful stories.

“I simply want to say thank you to all of those people who have touched me so deeply throughout my career.”

Ebersol has been something of a lifer at NBC. When he was 28, Ebersol was vice president of late-night programming and, with Lorne Michaels, developed “Saturday Night Live.” He left for a time, then returned as executive producer of “SNL” in 1981 and stayed until 1985. He worked on his production company until returning to the network in 1989.