By Erik Malinowski, Photo by Mark Rabinowitz

May Day, 1991. Oakland Athletics left fielder Rickey Henderson stood near second base, slowly inching toward third. Everyone knew what was coming. The broadcasters up in the booth. Yankees pitcher Tim Leary. The rabid, 36,000-person home-field crowd. All that remained was the act. And so, without ever coming to a full stop, Henderson pivoted his right heel and successfully stole the 939th base of his then-12-year career. The crowd erupted. Henderson ripped third base from the dirt, shaking it above his head like a fresh kill. Lou Brock, the retired outfielder who had held the record for 14 years, came down onto the field and congratulated Henderson through a booming microphone. He passed the mic to his newly crowned heir, who wasted no time in anointing himself “the greatest of all time.”

It was hard to argue with the man.

When his 25-year career ended in 2003, Henderson had amassed 1,406 stolen bases—50 percent more than Brock. He had stolen the most bases of anyone up to age 29 (794) and the most of anyone over age 30 (612). He led the league in steals 12 times, including the single-season record in 1982 with 130—close to averaging one per game. Someone once asked renowned baseball historian Bill James whether he thought Henderson was a candidate for the Hall of Fame. James replied, “If you could split him in two, you’d have two Hall of Famers.”

There have been more beloved players than Henderson. Babe Ruth carried a weary nation through the Great Depression; Cal Ripken proved that the mere act of showing up for work every day for 16 years could unite a sport. But Henderson’s place among these titans of pastime is assured not by public adoration. It’s just that no one in baseball history was—and probably will ever be—better at stealing bases than Rickey Henderson.

After Henderson’s first full season, the league-wide average of stolen bases per game jumped 10 percent. As players began to emulate Henderson, success rates climbed toward 70 percent. The Henderson Effect leveled off at 0.85 steals per game in 1987—a 68-year high—and baseball began its sad transition to one of steroids and a “chicks dig the long ball”– induced myopia that hinders the game to this day.

Still, no matter if base-stealing happens to be in style, it remains the single riskiest behavior that a player can attempt on the diamond. In 2004 Joe Sheehan, an author of Baseball Prospectus, the annually updated bible for baseball stat-heads, found that unless a player snags at least three steals for every time he is caught—a 75 percent success rate—he shouldn’t even bother. Henderson’s career success rate was just over 80 percent.

Glory through speed did not come free. In 1982, when Henderson stole his still-unmatched 130 bases, he set another, hardly mentioned milestone. He was caught stealing 42 times—and 335 times in his career. Both are all-time records. And each time Henderson walked back to his dugout, muttering to himself, he was proof—in dirty cleats and jittery feet— that even the “greatest of all time” had to live with utter failure every now and then.