Sixty years ago this spring, a shy, skinny young black man from Mobile, Ala., entered his final season of minor league baseball in Jacksonville, Fla., before departing for the majors.

That young fellow would go on to have an extraordinary career -- arguably the greatest baseball career ever -- one in which he toppled the most glamorous and sacred record in all of American sports.

But Hank Aaron, now in the twilight of his life at age 79, has never enjoyed the popularity or acclaim of either the man whose home run record he shattered, Babe Ruth, or his most prominent contemporary and rival, Willie Mays.

Indeed, Aaron - who endured reams of racist hate mail in the lead-up to his breaking of Ruth’s record in 1974 -- has even been overshadowed by lesser talents during his career. Part of this diminished appreciation can be attributed to the fact that he played in small-market teams (Milwaukee and Atlanta), but also to his decidedly shy, awkward and rather dull persona.

Blessed with immense talent, Aaron nonetheless lacked the sheer exuberance and unmatched charisma of Mays, the movie star looks of war hero Ted Williams, the monstrous home runs and New York spotlight of Mickey Mantle, the tragic nobility and exoticism of Roberto Clemente and the massive blue-collar appeal of Carl Yastrzemski and Pete Rose.

Despite such “shortcomings,” Aaron pieced together a career of amazing -- almost superhuman -- consistency, which, combined with the absence of significant injuries, allowed him to carve together statistics that made him a baseball immortal: .305 career batting average, 755 home runs, 3,771 hits, 2,297 runs batted in, 6,856 total bases and 1,477 extra-base hits (the last three of which are still Major League records). Most of his other important offensive statistics are in the top five of baseball history.

But for the majority of his career, Aaron seemed to exist in the shadows -- he really never had an individual “breakout” year, he simply delivered the same excellent numbers year after year in a workmanlike manner.

“[Aaron] was an incredibly consistent performer over the years, but never had a massive standout season that would have instantly elevated him,” said Tom Stanton, the author of a number of books on baseball.

“He was by nature neither a flashy person nor a publicity-seeking star, which meant he was often in the shadow of others, [even] including teammate Eddie Mathews in the 1950s.”

Consider the amazing -- but perhaps mundane -- consistency of his career. He delivered 17 consecutive seasons in which he had 150 or more hits, but only three where he broke the magic 200-hit barrier (twice early in his career).

Despite his fame as a slugger, between 1955 and 1970, his home run totals varied between 24 and 44 -- never breaking 50 like his peers Mays and Mantle did. (In 1971, when Aaron was clearly trying to hit more home runs, he stroked a career high 47 at the age of 37). He also hit 30 or more homes runs a record 15 times.

In addition, noted former Newsday sports columnist Stephen Jacobson, Aaron’s home runs were typically line drives that just barely cleared the fence -- not the majestic, titanic, soaring trajectories that made Mantle a living legend and an instant fan favorite. 

“Also, Aaron did not hit monumental home runs, his hat did not fly off his head as he ran the bases, a la Mays, and he enjoyed no great peak as a player,” Jacobson noted.

Moreover, Aaron only won one World Series (in 1957), three Gold Gloves, two National League batting titles, and (despite the huge career numbers), “only” four NL home run championships. Aaron also nabbed just one MVP award -- again, in 1957.

Playing in relative obscurity for the first 18 or 19 years of his career -- as “obscure” as a superstar can be -- Aaron became a national sensation when it appeared it would be him (and not the more popular Mays) who would break Ruth’s sacrosanct career record of 714 home runs.

“By the time Aaron broke the home-run record, he was a massive star, receiving more mail than anyone in the United States [other] than the president,” Stanton stated.

“Still, a career in [a media center like] New York would undoubtedly have added to his cache -- and probably made him a bigger name earlier.”

The home run record had stood unchallenged for almost 40years, defying efforts by a number of sluggers -- including Ted Williams and Jimmie Foxx -- from coming anywhere near it.

But as a black man, Aaron’s ascension to the most hallowed ground in American spots triggered resentment from many white racists, who bombarded him with hate mail and even death threats, thereby ruining what should have been his shining moment. All the letters of admiration and congratulation apparently could not alleviate the fear and worry the hate letters spawned in Aaron and his family.

Still, when Aaron hit No. 715, Dodgers announcer Vin Scully spoke for many when he exclaimed:  "What a marvelous moment for Atlanta and the state of Georgia; what a marvelous moment for the country and the world. A black man is getting a standing ovation in the Deep South for breaking a record of an all-time baseball idol. And it is a great moment for all of us.”

Indeed, Aaron’s career not only paralleled the growth of the U.S. civil rights movement, it also coincided with a transition in the National League from being an all-white league of slow, lumbering sluggers to a more dynamic, speed-oriented game featuring an infusion of exciting new black and Hispanic players.

In the nearly four decades since Aaron’s retirement, he has received numerous awards and laurels, including near-unanimous enshrinement in the Hall of Fame, the Presidential Medal of Freedom, the country's highest civilian honor and important jobs in the Braves’ front office.

However, certain controversies and surprising revelations have also dogged the great Braves slugger.

For example, in August 2007, when Barry Bonds broke his career home run record, Aaron refused to attend the game when the historic No. 756 went out of the ballpark in San Francisco (although Aaron did appear in a tape recorded message on the scoreboard). Media speculated that Aaron did not want to validate an accomplishment that many suspected was tainted by Bonds’ alleged use of performance-enhancing drugs.

Jacobson speculates that not only does Aaron resent his record being broken, but is further maddened that it was shattered by someone suspected of cheating.

Moreover, the true nature of Aaron’s relationship with Bonds’ godfather, Willie Mays, has also come under the microscope.

In 2010, a biography of Aaron by Howard Bryant ("The Last Hero: A Life of Henry Aaron"), revealed that the two baseball greats did not enjoy a friendly relationship, either before or after Aaron became the all-time home run king.

"Willie would never surrender the stage easily to the man who had always played in his shadow,” Bryant wrote.

“They were not friends… there was always something about Willie that wouldn't allow a real friendship with Henry. Willie wouldn't, or couldn't, ever give Henry his due as a great player, and that inability on Willie's part to acknowledge Henry as an equal was what really burned Henry… When Henry began to soar up the home-run chart, Willie was loathe to give even a partial nod to Henry's ability, choosing instead to blame his own performance on his home turf, Candlestick Park, saying it was a lousy park in which to hit homers and this was the reason for Henry's onrush."

Bryant put the blame for this fractious relationship squarely on the shoulders of Mays, whom he called “cruel” and “self-centered,” rather than on the “diplomatic” Aaron.

Bryant also cited an incident as long ago as 1957 when Mays humiliated the young sensitive Aaron in public by calling him a  “dumb n__ger!"

In response, the shy and reserved Aaron did not retaliate against Mays, but remained cold and distant from his cross-country rival over the decades.

Even in a joint TV appearance with Bob Costas on HBO in 2008, Aaron simply smiled and stayed cordial, while Mays waxed nostalgic about their (apparently nonexistent) friendship.

Mays (whose sullen and unpleasant personality has been documented by umpteen journalists and fans over the years) likely resents Aaron for breaking Ruth’s record -- something Mays might have done himself had he not lost almost two years of his career to military service. Given that Mays finished with 660 homers (while missing most of the 1952 season and all of 1953), he potentially could have tied or set the home run record as early as 1971, three years before Aaron did.

However, Stanton cautioned that it would be an exaggeration to claim that Aaron and Mays were in any way enemies.

“Though both grew up in Alabama, they were different individuals, different personalities,” he said.

“But they did not dislike one another.”

Stanton does concede that Mays was likely jealous that Aaron surpassed Ruth in homers and not the "Say Hey Kid."

Aaron has also been mildly critical of what he perceived as Mays’ lack of involvement in the civil rights struggle.

In a biography called "Willie Mays: The Life, The Legend," author James Hirsch quoted Aaron as complaining: "If any part of me was not satisfied with Willie, it's that he didn't speak out enough [on the issue of civil rights]. I couldn't understand that part of it. I never spoke to him about it. I just let it be.”

Since retiring, Aaron has been vocal about such issues as the dearth of blacks in baseball front offices as well as the declining number of blacks on the field, as baseball loses the best talent to football and basketball.

Jacobson, author of “Carrying Jackie’s Torch” (which documented the struggles of the first generation of black Major Leaguers) further noted that Aaron is far more articulate than Mays, who was suspicious of interviewers and feared embarrassing himself, often turning down requests to speak to reporters. In contrast, the well-spoken Aaron was quite willing to discuss issues far outside of baseball with the media.

Stanton, whose baseball books include “Ty and The Babe” (which documented the complex relationship between two baseball legends of an earlier era), explained that Aaron stood up for his civil rights in the 1960s, in an atmosphere of intense racism, particularly after meeting his future wife, Billye.

“But you can see evidence of his standing up to prejudice [as long ago as] in the early 1950s,” Stanton noted.

“On one occasion, for example, he refused to abide a photographer who asked him to pose eating a watermelon.”

One must also wonder if Mays -- also a black man, but far more popular than Aaron -- would have received the kind of hate mail that Aaron was deluged with had he (Mays) broken Ruth’s record first.

Mays, who suffered from the slings of racism for much his early career (even as a veteran in San Francisco, when realtors refused to sell him a house in a white neighborhood), likely would have also received scurrilous mail, Stanton believes.

“Aaron’s situation was compounded by the fact that his home team was based in the South -- in Atlanta -- at a time when Georgia still had a segregationist for governor [Lester Maddox],” he noted.

Now, in 2013, with the recent death of Cardinals icon Stan Musial, who, like Aaron, played in the shadows of more glamorous peers for much of his career -- and the passing of Joe DiMaggio and Ted Williams over the past dozen years -- the mantle of greatest living ballplayer must fall upon either Mays or Aaron.

Many fans and media insist that Mays is not only the greatest living player, but also the greatest all-round player in history. However, a strong argument could also be made for the quiet man from Mobile, the ballplayer who actually holds all the important records, if not the adulation and acclaim.

Jacobson suggests that Aaron’s true legacy is that of a “truly decent sportsman” and “superb ballplayer” who nonetheless will always be overlooked and overshadowed by Mays.

“I think that among the cognoscenti and baseball experts, Aaron is highly respected and even revered, but among the average fan, not as much as Mays or Mantle,” he said.