Peg Millar said he died at his Houston-area home Nov. 30, ending a nearly four-year struggle against bile-duct cancer, the Los Angeles Times reported Sunday.
Millar came up with the concept for "Tank McNamara," about a former pro football player turned TV sportscaster in 1974, writing the text while collaborator Bill Hinds provided the artwork. It now runs in about 150 newspapers.
Hinds said Millar approached him about doing something "satirical and sardonic" like "Doonesbury," but with a sports angle, the Times said.
"Jeff's perspective was outside of sports looking in," Hinds said. "When you're inside, you can't see how crazy it is."
The strip tackled many contemporary issues through the years, the newspaper said, including drunken driving, sexual scandals,coaches' foibles and even Michael Vicks' dogfighting case.
"He wanted to go cutting-edge," Peg Millar said. "He wasn't too worried about how he was perceived."
In the early '90s, Millar told the Seattle Post-Intelligencer, "There is no hands-off subject."
Besides his wife, Millar is survived by five siblings.