Jack Klugman, the rubber-mugged character actor who leapt to television stardom in the 1970s as the slovenly sportswriter Oscar Madison on “The Odd Couple” and as the crusading forensic pathologist of “Quincy, M.E.,” died on Monday at his home in the Woodland Hills section of Los Angeles. He was 90.

His death was confirmed by his stepson Randy Wilson.

At one time a heavy smoker, Mr. Klugman had survived throat cancer, which was diagnosed in 1974. After a vocal cord was removed in 1989, his voice was reduced to a gravelly whisper.

Mr. Klugman, who grew up in a rough-and-tumble neighborhood in Philadelphia, wasn’t a subtle performer. His features were large and mobile; his voice was a deep, earnest, rough-hewed bleat. He was a no-baloney actor who conveyed straightforward, simply defined emotion, whether it was anger, heartbreak, lust or sympathy.

That forthrightness, in both comedy and drama, was the source of his power and his popularity. Never remote, never haughty, he was a regular guy, an audience-pleaser who proved well-suited for series television.