Off Keswick Avenue in Glenside rests a lovely little baseball field at Renninger Park. There is a story told there, among local-league and travel-team coaches and players and parents, about Reggie Jackson. The story may be apocryphal, a legend that sounds true and one might wish were true but really isn’t true. No one there knows.

Beyond the field’s right-center-field fence, some 300 feet from home plate, rests a lovely little community swimming pool, with stumpy lifeguard stands and blue-and-gold sun umbrellas that happen to share the colors of Jackson’s alma mater: Cheltenham High School. When Jackson was 12 years old, according to the legend, he launched a home run that splashed down into that pool.

He is 75 now. Such things can be harder to remember, if they happened at all.

“I always hit the ball farther than everybody else,” he said recently over the phone. “I always hit the ball a longer distance in high school, Little League, American Legion.”

Then he said it again: “I always hit the ball farther than everybody else.”

A modern moment in the distant past

In 1971, Major League Baseball did not have interleague play, or even the designated hitter, and because an ingenious entertainment executive had not yet thought to turn the NFL offseason into a daily television drama to rival the ratings of Bonanza or All in the Family, the All-Star Game – the “Midsummer Classic” – possessed a resonance that seems outsized, even alien, today. Carl Hubbell using his screwball to scythe through the meat of the American League lineup in 1934, Ted Williams clocking Rip Sewell’s “eephus pitch” over Fenway Park’s right-field wall in 1946, Pete Rose plowing over Ray Fosse in 1970: These episodes were significant, even in a game that was irrelevant to the standings, because of the reality and the attraction of seeing the best against the best.

The 1971 game – played on July 13 at Tiger Stadium in Detroit, 50 years ago Tuesday – marked perhaps the apex of that long-faded tradition. Eighteen players who went on to be inducted into the National Baseball Hall of Fame appeared in the game, and it marked the last time an All-Star Game’s two starting pitchers – the Pirates’ Dock Ellis and the A’s Vida Blue – were Black.

All the runs scored in the American League’s 6-4 victory came on home runs, and all six of those home runs were hit by future Hall of Famers: Johnny Bench, Hank Aaron, Frank Robinson, Harmon Killebrew, Roberto Clemente, and Jackson. It was a flash of modern baseball in what is now the distant past, a prelude to what the sport would become: power, all power, nothing but power. Only one of those home runs, though, remains the most memorable in All-Star Game history. Only the one that Jackson hit.

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Jackson had grown up in Wyncote immersed in baseball. His father, Martinez, who owned a tailor shop, had been a second baseman for the Newark Eagles in the Negro National League, and whenever Reggie was at practice for the Glenside Midget Baseball Team or for Cheltenham, Martinez would finish his dry-cleaning delivery route and park his truck beyond the left-field fence, to check on his son’s progress. As a 14-year-old, wearing his GREATER GLENSIDE jersey, Reggie had struck out looking in his only at-bat during a Pennsylvania-vs.-Florida All-Star Game. He walked the 2 miles home from the field by himself, crying, vowing that he would be a big leaguer someday. He lettered in four sports in high school and earned a football scholarship to Arizona State, but he knew his athletic future lay at the end of only one road.

“Baseball is my sport,” he told The Inquirer in 1964. “I love the game.”

The arc of his career, his familiarity with baseball’s history, and his considerable ego combined to make him anxious ahead of and during his appearance in the 1971 All-Star Game. In 1969, when he was 23 and in his second season with the A’s, Jackson had put together what would turn out to be the best statistical season of his 21 years in the majors – 47 home runs, 123 runs scored, a 1.018 on-base-plus-slugging percentage – only to regress in 1970. He missed much of spring training because of a contract holdout, finished with just 23 home runs, and saw his batting average plummet 38 points, to. 237.

He had bounced back in ’71, batting .272 with 17 home runs at the All-Star break. But he was still a young player, unproven, brash for baseball’s staid culture, and Orioles manager Earl Weaver hadn’t planned to select him for the American League team until June 29, when the Twins’ Tony Oliva stepped on an outfield drain in a game against the A’s at Oakland Coliseum and injured a knee. Jackson replaced Oliva on the roster.

In the clubhouse after the A’s final game before the break, Jackson, whose nickname at the time was “Buck,” began packing for Detroit. One of his teammates, third baseman Sal Bando, gave him a warning. It was playful, partly.

“Bando says to me, ‘Buck, whatever you do, don’t strike out and embarrass the team,’ ” Jackson said.

‘Wow, did I do that?’

During the pregame portion of NBC’s coverage, play-by-play announcer Curt Gowdy noted that a 30-mph wind was blowing from home plate toward Tiger Stadium’s outfield fence. Looming above the fence, in right field, were skyscraping, tiered bleachers topped by a light tower on the third deck. The wind’s effect quickly became obvious when Bench socked a two-run home run in the second inning and Aaron lofted a solo shot in the third, both to right-center.

After Luis Aparicio singled to lead off the bottom of the third, Weaver sent Jackson up to pinch-hit for Blue. You’re going to waste me early? Jackson thought. Save me for the big moment! Wielding a massive 37¼-ounce bat, custom made for him by Rawlings Adirondack, called a 288RJ – “I thought I was all hot [stuff] because I had my initials on the knob,” he said – he strode to the plate ... and fell into an 0-2 hole.

One of Jackson’s trademarks was his vicious, all-or-nothing left-handed swing. His 2,597 strikeouts are the most in major-league history. “I led the world in strikeouts, bro,” he said. But this time, his approach was different. All these future Hall of Famers were there, watching him, and Bando had said what he had said, and to strike out in this setting would be a humiliation that Jackson couldn’t abide. “I was a little nervous,” he said. “It was loaded with guys.” So he did something rare. He choked up on the bat.

Ellis fired a fastball wide of the outside corner, moving the count to 1-2, then threw a slider that didn’t break, that sat there, fat as the sun in the sky.

“I hit this ball right on the screws, and I know it’s gone because you don’t even feel it,” Jackson said. “You just go, ‘Wow, did I do that?’ ”

Ellis turned around, trying to track the ball’s flight, but he couldn’t find it. “I didn’t know what was happening,” he and Donald Hall wrote in Ellis’ autobiography, In the Country of Baseball. “Usually when it’s a home run, you see the fans reaching for the ball. I didn’t see them.” On the telecast, Gowdy told the rest of the country where the ball had gone. “It is … off the roof!” he said. “That hit the transformer up there.”

Six-hundred feet, 123 mph

Rick Gosselin, who that spring had been named sports editor of Michigan State University’s student newspaper, had, on a lark, sent a letter to the Tigers, requesting a media credential for the game. They had given him one. His seat was in the auxiliary press box, at the top of the stadium on the third-base side, across from and at eye level with the light tower that Jackson had just dinged.

“When Reggie hit it, it was like a slingshot,” said Gosselin, who has spent the last 50 years in sports writing, a career most notable for his coverage of the NFL and the Dallas Cowboys at The Dallas Morning News. “Put a pebble in a slingshot and let it go. See how it kind of explodes off? That’s what that looked like. I swear that ball was still climbing.”

As Jackson rounded the bases, he passed second-base umpire – and NBA referee – Jake O’Donnell, a Delaware County native. The two had met a few years earlier, when O’Donnell was beginning his umpiring career in the minors and Jackson was playing for the Birmingham Barons.

You got all of that, didn’t you, Reggie? O’Donnell said.

I got all of it, Jake, Jackson replied.

“It just was so loud,” O’Donnell said in a phone interview. “Who knows how far that would have gone, the way he hit that?”

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An Associated Press story, published two days after the game, estimated that the home run was 600 feet. A 2006 New York Times article said 520. Jackson, who worked as an adviser to the Yankees from 1993 until earlier this year, when he took on a similar role with the Astros, has been told that the ball traveled between 560 and 580 feet. He said that a Yankees statistician/analyst once calculated that, based on where it went and how long it took to get there, the ball left Jackson’s bat at an exit velocity of 123 mph.

When it fell to the grass, Willie Mays, standing in center field, picked it up and tossed it in toward the American League dugout. Jackson kept it and gave it to his father.

The power of power

Jackson was on five teams that won the World Series. He was named the American League’s Most Valuable Player in 1973 with the A’s. He was named World Series MVP that year and again in 1977, when, in the Yankees’ clinching Game 6 victory, he slammed three home runs on three consecutive pitches. There’s a reason everyone remembers him as “Mr. October” and only he remembers himself as “Buck.”

Still, he will call you back to talk about that home run from a half-century ago because he is always willing to talk about his favorite subject: Reggie Jackson. He regards that home run as an essential aspect of his legacy. “Which,” he said, “is awesome for me. I was so proud to round the bases. I went back in the dugout, and there was Al Kaline and Carl Yastrzemski and Frank Robinson. I had played winter ball with Frank, and he had mentored me. It was such a wonderful, awesome experience. Everybody congratulated me.

“I love it and enjoy talking about it. Tell them I did it all for Broad Street, William Penn, Cheltenham, Elkins Park, and Wyncote.”

He will call you back because he always hit the ball farther than everybody else, no matter how old he was or where the field was or who was on the field with him, and neither he nor anyone else may have ever hit a ball farther than he hit that one.

He will call you back because the legend around that home run isn’t really a legend. It’s all true, available for anyone to access and verify: the pitch, the swing, the gunshot crack of the bat, the buzz of the astonished spectators. And if you were the man who made such a moment happen, wouldn’t you want to relive it as often as possible? Wouldn’t anyone?

“Baseball is a game we can all relate to,” he once said. “It’s the American game. And the power ... who doesn’t dream about power? I know that’s what I love about hitting. It’s a show of strength. It’s two against one at the plate, the pitcher and the catcher versus you. When I’m up there, I’m thinking, ‘Try everything you want. Rub up the ball. Move the fielders around. I’m still gonna hit that ball.’ God, do I love to hit that ball out of the park and hear ‘em say, ‘Wow.’ ”

That sound is a drug. It always was. Reggie Jackson craves and savors it still, 50 years after the one everyone remembers, he himself most of all.