Carl Weathers, the actor who played Apollo Creed in four Rocky films, died on Thursday at the age of 76.

Weathers “died peacefully in his sleep,” a family statement obtained by the New York Times said, though a cause of death was not announced.

Weathers, who was born in New Orleans on Jan. 14, 1948, had some minor film and television roles, but it was his 1976 breakout role as Apollo Creed that brought his career to a new level. Based on the braggadocios Muhammad Ali as he went into battle against likable no-hoper Chuck Wepner, Creed did battle with Rocky (played by Sylvester Stallone) in the first two films, before becoming a friend and training partner to Ali in the third and fourth films.

Though Creed’s character dies in Rocky 4 at the hands of Ivan Drago, the character lives on through the three Creed movies, starring Michael B. Jordan as his son Adonis Creed.

Ali embraced the similarities between himself and Creed, surprising Stallone on stage at the 1977 Academy Awards with playful jibes saying “I’m the real Apollo Creed” before the two shadowboxed briefly.

Weathers shared a story with AllAccess about running into Ali on Rodeo Drive in Los Angeles and playfully sparring in the middle of the street to the amusement of gathered spectators.

Away from the screen, Weathers had his own athletic career. Standing 6’2” and weighing 220 pounds, Weathers played college football as a defensive end for Long Beach City College and San Diego State University, where he also earned a master in theatre arts. He went undrafted but signed with the Los Angeles Raiders in 1970, helping them win the AFC West division title. He later played in the Canadian Football League from 1971-73.

Among Weathers’ other movie credits are roles in the Adam Sandler films “Happy Gilmore” and “Little Nicky” as well as 1987’s Predator.

In an emotional Instagram video, Stallone paid tribute to his colleague.

“My life was forever changed for the better the day I met Carl Weathers. Rest in power and keeping punching,” said Stallone.

Weathers is the second veteran of the Rocky films to die in recent months.Burt Young, who played Rocky’s brother-in-law Paulie Pennino, died last October at age 83.