Ken Norton Sr., a former heavyweight boxing champion who beat Muhammad Ali once — breaking his jaw — and fought him to two other extremely close decisions, died Wednesday at a care facility near Las Vegas. He was 70.

Norton had been in poor health in recent years after a series of strokes, but the congestive heart failure he suffered Wednesday stunned those close to him, "like a sucker punch to us all," said Norton's close friend from Orange County, Patrick Tenore Sr.

One of Norton's four children, former UCLA and NFL linebacker Ken Norton Jr., who is now a Seattle Seahawks assistant coach, confirmed his father's death to the Associated Press.

George Foreman, another fighter from boxing's golden era of heavyweights, remembered Norton in a telephone interview with The Times on Wednesday.

"It's a sad day, but I take solace that I had the chance to be friends with him," Foreman said. "All of us from that time, Ali included, realized we should've enjoyed each other more when we were fighting. But at least we caught up."

Norton retired after losing by technical knockout to Gerry Cooney in 1981 with a record of 42-7-1 with 33 knockouts.

Norton became a member of the International Boxing Hall of Fame in 1992 by standing as the most complex opponent in Ali's career.

The muscular Norton confounded Ali with an awkward, inside fighting style, breaking Ali's jaw in their first meeting March 31, 1973, at the San Diego Sports Arena, a bout that Norton won by split decision.

They fought twice more, with Ali claiming a split decision victory Sept. 10, 1973, at the Forum in Inglewood, and a narrow unanimous decision Sept. 28, 1976, at New York's Yankee Stadium.

"Kenny Norton versus Ali was the textbook example of the phrase 'styles make fights,'" veteran boxing publicist Bill Caplan said. "You could've raised Kenny's hand as the winner in both the second and third Ali fights. He's in the club of the top four heavyweights of that era. They all did great round robins with each other."

Foreman impressively retained his World Boxing Council and World Boxing Assn. belts with a second-round technical knockout of Norton in Caracas, Venezuela, in 1974, a defeat made worse, Caplan said, by the fact that a government insurrection led officers to demand $75,000 from Norton (25% of his purse) before he could leave the country.

Norton emerged as WBC heavyweight champion in 1978 after then-new champion Leon Spinks declined to defend his belt against No. 1 contender Norton and chose to fight Ali for a richer purse. Given the belt, Norton lost his first defense against Larry Holmes on June 9, 1978, by split decision.

Kenneth Howard Norton was born Aug. 9, 1943, in Jacksonville, Ill. He was a four-sport standout in high school before serving in the Marines from 1963 to '67.

It was his humor, good-natured spirit and class that Foreman recalls.

"He fought Ali through those questionable decisions and even though he was patriotic, he never used that against Ali after what he had gone through," Foreman said, referring to Ali's refusal to serve in the military during the Vietnam War. "That made me so proud of him. He was humane."

Norton's friend Tenore said the boxer didn't bemoan the close losses, even in later years. When Tenore asserted that notorious promoter "Don King won the other two," Norton would respond, "No, I just got beat," Tenore said. "Never a bad word about people, never looked back."

He had an occasional acting career beginning in the 1970s, appearing in movies and TV series. Despite a car crash in the 1980s that left him in a coma and with a speech problem, Norton relished gatherings like an autograph signing a few years ago at the MGM Grand in Las Vegas with fellow heavyweights Joe Frazier, Earnie Shavers and Ron Lyle.

Norton fell on hard financial times during the last decade, but the WBC recently started mailing him monthly pension payments, Caplan said, and Foreman said about a year ago that he spent $60,000 on a Ken Norton watch the WBC auctioned.

All the money went to Norton to help with his medical care, and Foreman saw that his daughter gave the watch to Norton's daughter.

"Ali always said he was the most beautiful one, but none of us — Ali included — would ever take our shirts off for pictures around Kenny," Foreman said. "He was indeed the fairest of us all."

Norton, who resided in Dana Point and Henderson, Nev., is survived by his wife, Rose Conant; his sons Ken Jr., Keith and Kenny John; and his daughter, Kenisha.

Norton will be buried in Jacksonville, Ill., and a memorial service in Orange County is being planned, Tenore said.

lance.pugmire@latimes.com

Twitter: @latimespugmire