If A. J. Liebling, who was born 100 years ago on October 18, had been a fighter, he would have been a skilled craftsman, renowned for his improvising intelligence.

He would have been Bernard Hopkins or Archie Moore.

Despite his obese, unathletic body, and small, delicate hands, Liebling did box in his younger days. And he cultivated friendships with the wisest trainers and cornermen of his era. Together these things gave him the insight that boxing was partly geometry – essentially about angles and distances.

Liebling appreciated the chess match aspect of boxing, its timing, spacing, pacing, rhythm, adjustments, and site-to-side foot movement to acquire better angles to hit and not get hit. If his boxing writing had a secret weapon, it was the insider wisdom he received from trainers like Charley Goldman, Whitey Bimstein, and Freddy Brown. They were his graduate school professors, and he dedicated his book “The Sweet Science” (1956) to these three spit-bucket Spinozas. In the dedication, he called them “my explainers.”

All three were hard-core New York characters who gratified Mr. Liebling’s passionate urbanism. They worked out of Stillman’s Gym on Eighth Avenue, where Goldman had sculpted Rocky Marciano into an invincible hitting machine.

I recently re-read all of Liebling’s boxing pieces (and most of his other work), and I discovered that I appreciate them much more now than when I first read them during the 1960s. When I was younger I was unduly intoxicated by the Hemingway and Jimmy Cannon school of drama, lyricism, and tough-guy sentimentality. I am better equipped now to savor Liebling’s sense of history, his wry stylistic grace, his leisurely pace and historical digressions.

In the same way I now better appreciate Dostoyevsky, Cervantes, Al Smith, Johnny Cash, and Ted Williams. Standards seem to matter more once you become immune to trendiness.

Liebling did not inflate a fight with false meaning, or cosmic significance. A fight was usually just a fight to Liebling, not some universal metaphor for racial empowerment or foreign policy or the destiny of a particular group. He was a diligent reporter and lucid thinker who described what he saw. He heard what was being whispered on the lower frequencies, as Ralph Ellison put it.

Liebling also did not tend to see a fight as a test of character and will or in psychological terms involving the unconscious. This was more the school of writers influenced and tutored by trainer Cus D’Amato in his 14th Street gym: Norman Mailer, Gay Talese, Pete Hamill, and myself.

Abbot Joseph Liebling invested his faith in technique and preparation – when it came to both writing and fighting. He was splendid on the seedy, marginal atmosphere of boxing – the gyms, the training camps, the gamblers, the saloons, the sparring partners, and the con men like Doc Kearns, who could have been Earl Long’s other brother.

Boxing was – and always will be – a convention of low life, and Liebling was the Gibbon of the grifters. Liebling’s versatility and productivity (18 books) also made him among the best press critics, war correspondents, food writers, and memoirists of Manhattan. Although in this low-life realm, he might have felt he could embellish and pipe a few quotes in the direction of emotional truth, which was the ethical norm for his era.

Liebling ranks as one of the three best American writers about boxing – along with Norman Mailer and Budd Schulberg. (It’s a bit of a shock to recognize that America’s three best boxing writers are liberal Jewish intellectuals.) There was also W. C. Heinz of the old New York Sun, who wrote the unforgettable boxing novel, “The Professional.” Jimmy Cannon was a deadline poet with an instinct for tragedy in the loser’s dressing room. And Murray Kempton’s occasional boxing columns are extraordinary.

But, Libeling’s remain the gold standard. His essays from the 1950s are like the old grainy footage of Sam Langford and Gene Tunney. There is a subtlety and serenity that makes you resent all the modern self-promoting bombast.

For a fight, Liebling would take the subway to Yankee Stadium, buy a midpriced ticket, and sit among the paying fans and banter with them as the action ebbed and flowed. Then he would compose a piece that even fans who had already watched the newsreels of the match would learn something new from.

Many writers have mistakenly credited Liebling with inventing the phrase, “the sweet science,” but it was actually coined by Liebling’s great hero, Pierce Egan (1772-1849). Liebling gladly and often attributed the phrase, “the sweet science of bruising,” to Egan, who he called, “The greatest writer about the ring whom ever lived. Hazlitt was dilettante, who wrote one fight story.”

Egan, who wrote about bare-knuckle bouts in England from 1812 to 1828, shaped Liebling’s style the way Ray Robinson shaped Muhammad Ali’s. Egan’s writing was reportorial, meandering, anecdotal, dandyish, intimate with the fighters, and finely tuned to the late fluctuations in betting odds. Liebling described Egan as a self-educated shakedown man, which was a compliment. He wrote, “Egan’s cockney characters, and his direct quotes of how they talked, were a direct gift to Dickens, who, like every boy in England, read the author Boxiana.”

It is an irony that the classic fistic essays collected in “The Sweet Science” were written between 1951 and 1955, just at the start of boxing’s long, slow, steady decline, begun by the home television, which killed off the local clubs, where apprentices could learn their craft. Liebling called television, “An electronic gadget that peddles razor blades.”

Another irony is that these pieces were published in the New Yorker, which was not exactly a working-class tabloid, although boxing, an immigrant working-class sport, has always had intellectual cult fringe.

But William Shawn let his star writers follow their passions, even if he didn’t understand them. By most accounts Shawn loathed violence, but not as intensely as he appreciated exquisite prose. When Liebling died at age 59 in 1963, boxing vanished from the pages of the New Yorker for 25 years.

Liebling’s most memorable pieces are accounts of the major bouts of his era: the bleeding Ray Robinson’s comeback knockout of Randy Turpin; the invincibly conditioned Marciano’s knockouts of Joe Louis, Joe Walcott, Ezzard Charles, and Archie Moore; and Archie Moore’s off-the-floor knockout of Harold Johnson. Libeling sensed what fighters and what fights to write about.

The Sweet Science occupied such a large part of Mr. Liebling’s emotional life that he worked it into most of his best books and magazine pieces. There are pugilistic digressions in “The Hon est Rainmaker” (1953), “Chicago: The Second City” (1952), and “The Telephone Booth Indian” (1942).

In “Between Meals” (1962) there is a dazzling digression describing a fight in Paris in 1927. In Liebling’s masterpiece, “The Earl of Louisiana” (1961), there is a flashback to a Pete Herman fight he saw in Madison Square Garden in 1921 when he was still at Dartmouth – and about to be expelled.

“The Earl of Louisiana” opens with the memorable sentences, “Southern political personalities, like sweet corn, travel badly. They lose flavor with every hundred yards from the patch.”

If there is one weakness in Liebling’s boxing canon it is that the mob does not exist – and gangsters ran boxing in the 1950s. He let Cannon in the Post, Dan Parker in the Daily Mirror, and Schulberg expose the gangsters who fixed the fights and cheated the fighters. Liebling liked low life, but not the really sinister criminal dark side.

By contrast, Liebling’s populist press criticism had more of an irreverent, crusading edge; he was much more skeptical of newspaper publishers than of boxing promoters. He tracked the influence of money on newspaper content better than he tracked the influence of money on which fighters got on television or received preferential treatment in getting championship opportunities.

After immersing myself in Liebling’s writing, I see that he and his New Yorker colleague Joseph Mitchell invented what others branded the “New Journalism” and credited to Tom Wolfe and Hunter Thompson. If there was anything new after the 1940s it was the innovative elaborations of Mr. Mailer, Jimmy Breslin, and Mr. Talese.

But the real leap forward into long form, personal, literary narrative was started by Liebling and Mitchell. They opened a new house for the rest of us.

A wise man once told me that the definition of craft is the ability to make something hard look easy. This is what A.J. Liebling did. He made writing a sweet science.