CLEVELAND -- Jim Donovan, the beloved radio play-by-play announcer for the Cleveland Browns and a TV sports fixture for more than four decades, died Saturday. He was 68.

Donovan retired from his broadcast career earlier this year and stepped away from his game-day duties with the team before this season while battling cancer. He had called Cleveland's games since the team's expansion rebirth in 1999.

"This is an incredibly difficult day for us and the entire Cleveland Browns organization," Browns owners Dee and Jimmy Haslam said. "His impact as the Voice of the Browns for 25 years is immeasurable as he touched the lives of our fans each and every Sunday with his love for the Browns and his brilliance at his craft.

"He will be greatly missed, but he cemented a legacy that will live on forever. The only thing that outweighed his love for this city and this team was the love he had for his family. Our thoughts and prayers are with his wife, Cheryl, his daughter, Meghan, and everyone who was fortunate enough to call Jimmy family or friend."

A Boston native known to everyone as "Jimmy," Donovan endeared himself to Cleveland fans with his passion, sense of humor and professionalism. He was a stickler for detail, spending countless hours preparing for game broadcasts.

Donovan had recently been inducted into the Browns' Legends Club and the Greater Cleveland Sports Hall of Fame. He had been too ill to attend the events.

When he was forced to step down in August, Donovan wrote a letter to Browns fans expressing his gratitude for their support.

"I have called Browns games for 25 years. Not a day has gone by when I haven't paused and been so proud to be 'The Voice of the Browns,'" he wrote. "Cheryl, Meghan and I thank you for all the love, support and prayers during my rough patches. It's like having a huge family around us. And that's what makes the Cleveland Browns so special. You do."

Donovan had to step away as sports director at WKYC-TV last fall for several months to undergo treatment for leukemia. He returned to the broadcast booth in time to call the team's late-season run to the playoffs.

He had been diagnosed with chronic lymphocytic leukemia in 2000 and underwent a bone marrow transplant in 2011.

A graduate of Boston University, Donovan got to Cleveland in 1985. Along with doing local reporting of the city's three professional sports franchises, Donovan also had several national network assignments and was part of NBC's coverage team at the 1992 and 1996 Summer Olympics.