On Sunday afternoon, with two outs in the top of the first inning, José Ramírez stole second base standing up. It was an easy swipe—on a low ball, with no throw from the catcher—and it didn’t amount to anything once Yandy Diaz grounded out to end the inning. Still, it granted a minor piece of history for Ramírez. It was his 30th steal of the season, making him the first man in six years to enter baseball’s 30-30 Club.
Ramírez likely won’t be the only player to gain membership this year; Boston’s Mookie Betts is right behind with 29 home runs and 27 stolen bases. As recently as a few years ago, it didn’t feel at all remarkable to see multiple players achieve the feat in one season. From 1995 to 2012, at least one player completed the feat, and more often than not, the count was even higher. In 12 of those 18 seasons, two or more players enjoyed entry into the 30-30 Club. Since 2012, though, there have been none. It doesn’t take much sleuthing to figure out why: As home run totals have spiked, stolen bases have been on a sharp decline.
At a glance, that isn’t a groundbreaking insight. The game’s stylistic shift has been profound enough for even the most casual fans to notice. But there’s something compelling here, all the same—in the intensity of the current pattern, in how quickly it’s taken hold, and in how it fits a herky-jerky history of basestealing.
The first player to steal 30 bases and hit 30 home runs in a season was the St. Louis Browns’ Ken Williams in 1922. No one would do it again for more than three decades, until Willie Mays pulled it off in 1956 and again in 1957. A little bit later, there was Bobby Bonds, who did it a record five times from 1969 to 1978. By the time that he retired in 1981, the feat had been accomplished ten times by five different players. In the ‘80s, though, the club’s entryway filled up—gaining six new members, including José Canseco, who became the first man to go for 40-40. And in the ‘90s, as power and speed increased alike, the doors were flung wide open, with 20 individual seasons of 30-30. (Barry Bonds claimed five of those, tying his father’s record.) The ‘00s kept it going, though not quite at such a breakneck pace. And then, six years ago, the doors shut. Baseball hadn’t gone so long without an entry into the club since the gap between Hank Aaron in 1963 and Bobby Bonds in 1969.
The last few years might have seemed like fertile ground for 30-30. In 2016, second basemen hit a record number of home runs, and shortstops did, too. In 2017, everyone hit a record number of home runs—1.26 per game, a marked jump above the previous high of 1.17. With that sort of power, particularly from traditionally speedy up-the-middle talent, how could there not have been so much as one player in reach of 30-30? Simple:
The 2018 rate of stolen bases per game currently sits at .50, the result of a half-decade downturn and the lowest that it’s been since 1972.
That might seem like just another step down the one-way street leading to maximum efficiency of play. Front offices are smarter than they were a decade ago; so, too, are managers. A stolen base’s risk and reward are common knowledge, captured in explicit numbers. This is just smart baseball, or, at least, what “smart baseball” is right now. But there’s more to it than that. The running game is an area of baseball that’s always been volatile, subject to extreme bouts of ebb and flow. “Stolen bases have come and gone throughout baseball history because they are a sort of trendy item, an offensive trinket that has attracted managers at times but has been blithely ignored by them at others,” Bill James wrote in SI in 1982, in a piece accompanying a profile of Rickey Henderson’s 130-steal season. In the intervening years, not much has changed.
The current dip in stolen bases, for instance, hasn’t been enough to bring the rate anywhere near the all-time low. It’s almost double that: .26 steals per game, from 1950. Dom DiMaggio led baseball in stolen bases that season with just 15, and while the landscape didn’t stay quite that barren in the immediate future, the rest of the decade didn’t hold much more. Home runs were booming, and stolen bases weren’t en vogue. “Stealing didn’t exactly spring back overnight like a parched flower after a summer rain; the return of stealing was a long, slow process that, like almost everything else in baseball in the 1950s, seemed to move in slow motion,” Russell Roberts writes in Stolen!: A History of Base Stealing. Part of that slow growth? Before teams were willing to steal more, they had to steal better. At the time, a man was almost as likely to be thrown out as he was to gain the extra base. (The 1950 play-by-play data is incomplete, but stolen-base percentage hovered around 56% from 1953-55.) The risk-benefit analysis there doesn’t take much in the way of sophisticated arithmetic; with performance odds like that, why try?
A half-century later, Baseball Prospectus was around to crunch the numbers. From 2004: “If you’re stealing at less than a 75% success rate, you’re better off never going at all.” The game, as a whole, has never quite reached that point. But in recent years, it’s gotten close. The 12 most successful base-stealing seasons in baseball history are the 12 from 2006-18, with no exceptions. The success rate has ranged from 71.4 to 74.4%. (In 2018, it’s been 71.9%.) In other words—teams have been stealing bases better than ever before, and they’ve also been smart enough to know that they aren’t yet quite good enough to justify doing it even more.
The graph of basestealing trends looks more like a roller coaster than a circle, but it isn’t difficult to spot some cyclical motion. Right now, smart base-running means less base-running than it has in decades. But that definition is not a fixed point; it moves, relative to what other teams are doing and to how skill sets are developed. For now, though? Ramírez—Betts, too, perhaps—is the exception to prove the rule of the moment.