LOS ANGELES — Tony Burton, a veteran character actor best known for brief but memorable turns as a tough, no-nonsense trainer and cornerman in Sylvester Stallone’s first six “Rocky” films, has died at age 78.

Burton died of pneumonia Thursday at a Southern California hospital.

Failing health had prevented him from appearing in “Creed,” the seventh “Rocky” movie and the one for which Stallone is nominated for a best supporting actor Oscar at Sunday’s Academy Awards.

“People would always ask him, ‘What’s Sylvester Stallone like,’ his wife recalled with a chuckle. “He’d just say, ‘Sylvester’s a nice guy.’ That’s all he’d ever say.”

Burton, a former boxer himself, had a long career as a character actor.

He appeared in “The Shining” and “Stir Crazy” and was one of the ballplayers in the 1976 film “The Bingo Long Traveling All-Stars & Motor Kings.”

He was a regular in the TV series “Frank’s Place” and appeared in “Chicago Hope,” “The Rockford Files” and “Sanford and Son.” His last major film was 2006’s “Rocky Balboa,” in which he prepares the nearly 60-year-old Rocky Balboa character played by Stallone for an exhibition against the current champion, telling Balboa to “bring some hurtin’ bombs.”

In the first two Rocky films, his character, Tony “Duke” Evers, was trainer and manager to Rocky’s world-champion opponent, Apollo Creed, played by Carl Weathers.

Born and raised in Flint, Mich., Burton was a top Golden Gloves boxer in his youth and had a brief professional boxing career.

In addition to his wife of 36 years, Aurelain “Rae” Burton, he is survived by a son and two daughters.