Bert Sugar, boxing’s fedora-topped, cigar-smoking don of ringside sportswriters who was perhaps the most knowledgable and decidedly the most opinionated historian of the sport, died March 25 at a hospital in Mount Kisco, N.Y. He was 75.

He had lung cancer and died of cardiac arrest, said his daughter, Jennifer Frawley.

Mr. Sugar was a native Washingtonian whose interest in boxing began at the University of Maryland, where he sparred with little success. “I was the great white hopeless,” he once quipped. He was a New York advertising executive before pursuing a full-time sportswriting career in the 1970s.

In 1979, Mr. Sugar became editor and publisher of the Ring, widely regarded as the “boxing bible,” and also wrote and edited boxing publications such as Boxing Illustrated and Fight Game.

A maven of the facts, figures and statistics of sports, Mr. Sugar wrote more than 50 books about baseball, horse racing and football. (He was a master of sports trivia: “Who played for the Yankees, the New York Giants and the Knicks?” Mr. Sugar’s answer: “Gladys Gooding, the organist.”)

Mr. Sugar’s first passion, however, was what he called “the most ancient of sports, boxing.”

From his seat by the ropes, Mr. Sugar covered bouts between many of the greatest fighters of the past half-century. In a style as blustery as it was vivid, he wrote about matchups featuring Muhammad Ali, Joe Frazier and George Foreman.

Of Ali’s and Frazier’s third fight, the 1975 bout in the Philippines known as “The Thrilla in Manila,” Mr. Sugar wrote: “Some day, when ring historians gather ’round boxing’s smoldering campfire to tell stories of great fights, going all the way back to the time when spectators wore grapes in their hair and the lions ate the losers, one fight from that long laundry list will be remembered as having been one of the greatest two-sided fights in boxing history: Ali-Frazier III.” Ali won the fight by a technical knockout.

Mr. Sugar was a stalwart defender of boxing, despite its violence. In testimony before lawmakers on Capitol Hill, Mr. Sugar called boxing “the refuge of those seeking to escape their roots as youngsters from the tenements, the ghettos, the projects and the barrios.”

To that group of men, Mr. Sugar continued, boxing offered a “social staircase out of the mean streets” and a way “to gain full fellowship into our society by the only means of escape they possessed: their fists.”

Herbert Randolph Sugar was born June 7, 1936, in Washington. One of his first jobs was delivering copies of The Washington Post, and one of his routes included the home of Sen. Joseph R. McCarthy (R-Wis.), who launched anti-communist witch hunts and also was known as a heavy drinker.

“I would find him asleep on his front steps,” Mr. Sugar told the New York Times in 1995. “I’d stick the paper under his arm and ring the doorbell.”

Mr. Sugar graduated from Woodrow Wilson High School and, in 1957, from the University of Maryland. At the University of Michigan, he received a master’s degree in business in 1959 and a law degree in 1960.

He briefly practiced law before working for advertising firms including J. Walter Thompson and McCann-Erickson. In 1977, he turned to sportswriting full time. Two years later, Mr. Sugar and business partners — including Hall of Famer Dave DeBusschere, a star forward for the New York Knicks — bought Ring magazine.

Within five years, Mr. Sugar was fired by his partners after the publication failed to turn a profit. He sued them and in a 1987 settlement received ownership of Ring properties including Boxing Illustrated.

He frequently appeared on sports television programs on ESPN and HBO to discuss boxing in his authoritative and recognizable baritone.

Mr. Sugar stood out in boxing crowds. He wore a fedora no matter whether he was inside or out and was rarely seen without a drink in his hand and a foot-long cigar between his teeth. His business card listed his “office in exile” as Manhattan’s O’Reilly’s Pub, where he wrote columns on a typewriter in a back booth. New Yorker magazine once called Mr. Sugar the “best kibitzer in New York.”

With former light-heavyweight champion Jose Torres, Mr. Sugar co-wrote a 1971 biography of Ali called “Sting Like a Bee.” He also collaborated with Angelo Dundee, who died in February, for the boxing trainer’s 2008 memoir “My View From the Corner.”

Mr. Sugar wrote several books of lists that highlighted his affinity for hyperbole, including “Baseball’s 50 Greatest Games” (1986). He dedicated the book to his wife, “without whose help this book would have been finished four months earlier.”

Survivors include his wife of 51 years, Suzanne Davis of Chappaqua, N.Y.; two children, Jennifer Frawley of Pleasantville, N.Y., and John-Brooks Sugar of New York; a brother; and four grandchildren.

As the author of a horse-racing betting guide, Mr. Sugar once revealed his secret to picking a winner.

“I go over all the facts and the figures — I like to liken them to hieroglyphics — in the Racing Form and elsewhere, then spend considerable time doing my own handicapping,” Mr. Sugar told the Times in 2003. “Then I turn to the guy alongside me and ask ‘Who do you like?’ just like a lot of other bettors. Sometimes it even works.”