April 8 marks anniversary of milestones for Hank Aaron and Frank Robinson

Neil Leifer/SI Earlier today, The Strike Zone ran a Q&A with Pete Rose commemorating the 50th anniversary of his major league debut. As notable as that is,

Neil Leifer/SI

Earlier today, The Strike Zone ran a Q&A with Pete Rose commemorating the 50th anniversary of his major league debut. As notable as that is, the date is an even more important one in baseball history as the anniversary of two milestones that don't arrive this year accompanied by round numbers. On April 8, 1974, Hank Aaron hit his 715th home run, thus surpassing Babe Ruth as the game's all-time leader. Exactly one year later, Frank Robinson debuted as the first African-American manager in major league history, and a player-manager at that.

Aided by the hitter-friendly environment of Atlanta Fulton-County Stadium — at 1,000 feet above sea level, the majors' highest park at the time — Aaron put himself in position to pass Ruth by remaining a productive hitter well into his late 30s. From 1969, when the stadium shortened its power alleys, through 1973, he averaged an MLB-high 40.6 homers per year, not too shabby for a player in his age 35-39 seasons. He finished the 1973 season with 713 homers, and thus was forced to wait an entire offseason — one flooded with virulently racist hate mail, at that — to complete his chase.

Aaron began the 1974 season with a bang, homering off the Reds' Jack Billingham with his first swing of the bat on Opening Day (April 4) in Cincinnati. Controversy ensued as the Braves sat him for the next game in the hopes of prolonging the chase until they could return to Atlanta, but stuffed-shirt commissioner Bowie Kuhn demanded his restoration to the lineup lest the team face "serious consequences." Aaron went 0-for-3 in the final game of the series with the Reds before the Braves returned home.

Once he did, it didn't take him long to pass the Babe. After Dodgers pitcher Al Downing walked Aaron in the second inning, he left a high fastball in Aaron's wheelhouse in the fourth inning, and Aaron clobbered it into the Braves' bullpen in left centerfield, where it was retrieved by reliever Tom House. Aaron was mobbed by his teammates as he crossed the plate, and his parents joined the celebration as fireworks went off. Kuhn was notably absent from the proceedings, somehow winding up in Cleveland on that date. Instead the league office was represented by Monte Irvin, like Aaron a former Negro Leaguer.

This video features the famous call by Braves broadcaster Milo Hamilton, who until the end of last season last year was still calling games for the Astros. Not to be outdone, the Dodgers' Vin Scully's call was one for the ages as well. Once he informed viewers that the ball had gone out, Scully stayed silent for more than a minute and a half, letting the noise of the crowd and the accompanying bursts of fireworks tell the story. When he resumed speaking, he said:

“What a marvelous moment for baseball. 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 idol. And it is a great moment for all of us, and particularly for Henry Aaron.”

Aaron would finish his career in 1976 with 755 home runs and remain baseball's all-time home run leader until Barry Bonds surpassed him on August 8, 2007. The controversy surrounding the PED-tinged Bonds' chase led Reggie Jackson to hail Aaron as "the People's Home Run King" in a 2007 Sports Illustrated profile by Tom Verducci.

One year after Aaron's milestone home run, fellow slugger Frank Robinson carved his own special niche in baseball history. He had been acquired from the Angels via trade the previous September, and upon the dismissal of manager Ken Aspromonte at the end of the season, was soon named the team's player-manager. By the time he took the field in his first game at the helm of the Indians, it had been one week shy of 28 years since Jackie Robinson had broken the major leagues' longstanding color barrier and two and a half years since the great Dodger had called for MLB to employ its first black manager. Sadly, Jackie Robinson didn't live to see his protegé's debut, as he died of a heart attack nine days after making those comments.

Dressed in the Indians' garish all-red uniform, Robinson was in the lineup batting second as the team's designated hitter on Opening Day against the Yankees. In his first plate appearance, he homered off Doc Mecich, the 575th homer of his career, to help the Indians prevail 5-3. Though he hit a respectable .237/.385/.508 in 1975, the 39-year-old manager played himself sparingly, taking just 149 plate appearances in 49 games for the entire year. The Indians finished the season 79-80, a mild improvement over the previous year's 77-85 record, but yet another fourth-place finish in the six-team AL East.

Robinson's Indians climbed to 81-78 the following year — their first above-.500 finish since 1968 — though he played even more sparingly (36 games, 79 plate appearances) before hanging up his spikes at season's end. When the team got off to a 26-31 start in 1977, he got the axe. It would take him until 1981 to land another managerial job, and when he did so with the Giants, he became the first African-American manager in National League history — something of a dubious honor illustrating the game's lack of progress in that area.

So sparse were the ranks of African-American managers, in fact, that it took until June 26, 1989 for two teams with ones at the helm to square off; that day saw Robinson's Orioles meet Cito Gaston's Blue Jays. MLB's record in hiring African-American managers remains under scrutiny. At this writing, 16 such men have piloted clubs in 29 seasons, and only five have gotten jobs with a second team after their first tenure ended. For 2013, new Astros manager Bo Porter joins the Rangers' Ron Washington and the Reds' Dusty Baker as the only current ones.