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The Return of the Thief

The sport of baseball, at the major league level, is changing in many ways. The quickly escalating trend in strikeout rate has been well documented, and we’re now several years into a cycle where pitching and defense rule the day, but the league is evolving in other ways as well. Catchers are now hitting better than ever, for instance, and the lack of offense combined with the simultaneous shift in what teams value behind the plate may be leading to a renaissance of the stolen base.

As I noted in the Wall Street Journal yesterday, the success rate of stolen bases in 2014 is currently higher than it has ever been in MLB, and this isn’t simply a continuation of a shift towards conservative baserunning and the protection of precious outs. League caught stealing rates have been trending down for several decades as teams have learned that the hyper-aggressive running of the 1980s was likely counterproductive to run-scoring, but stolen base attempts are actually up this year relative to last year, even while the rate of runners getting thrown out continues to drop.

But even looking at league wide trends can obscure things a bit, as a large majority of players have no interest in attempting a stolen base no matter who the pitcher/catcher tandem might be, and changes in base stealing will be concentrated within a small subset of the player population. So, let’s just look at what we’ve seen among those who run the most.

Last year, Starling Marte was the league’s most aggressive base stealer (among qualified hitters) in terms of stolen base attempts as a percentage of his plate appearances; he ran 56 times and hit 566 times, giving him 9.9% stolen-base-attempts-per-plate-appearance. Eric Young and Jean Segura were also over 9%, while Leonys Martin, Jacoby Ellsbury, and Carlos Gomez were each over 8%. This year, however, the most aggressive runners are destroying those totals.

Dee Gordon has attempted 22 stolen bases on just 128 plate appearances, a whopping 17.2% SBA/PA. Billy Hamilton (15.7%), Rajai Davis (13.7%), Eric Young (11.1%), Ben Revere (10.6%), and Emilio Bonifacio (10.2%) are also attempting more than one steal per 10 trips to the plate, and Ellsbury, Martin, and Segura are continuing on right near last year’s marks. The average of the top 10 SBA/PA runners this year is 11.3%, with a median of 10.8%; the average of the 10 SBA/PA runners last year was 8.2% with a median of 8.1%.

Now, early in the season, you’re always going to have bigger spreads in rate stats than you will over an entire season. This is just the nature of smaller samples, as the spread from top to bottom shrinks as you get more data. But even isolating for just one month of data, we still see some pretty big changes from 2013.

Last April, Nate McLouth — yeah, I wasn’t suspecting that either — led MLB with an 11.5% SBA/PA rate, while no player attempted more than Ellsbury’s 12 stolen bases, at a rate of 10.6% SBA/PA. In any single month last year, the most aggressive base stealing belonged to Eric Young in July; he attempted 17 stolen bases on 121 plate appearances, a 14% SBA/PA month. Gordon already has five more stolen base attempts in just seven more plate appearances than Young’s month of July, and Hamilton is running more frequently as well despite rarely getting on base.

How about putting these marks in historical context? I pulled every player season from 1964 to 2013, giving us 50 years of seasonal stolen base attempt rates. Here is every season in the last 50 years with an SBA/PA north of 15%.

Season Name SBA SBA/PA SB%
1982 Rickey Henderson 172 26.2% 76%
1981 Tim Raines 82 22.6% 87%
1974 Lou Brock 151 21.5% 78%
1983 Rickey Henderson 127 20.4% 85%
1991 Otis Nixon 93 20.2% 77%
1980 Ron LeFlore 116 19.8% 84%
1985 Vince Coleman 135 19.5% 81%
1988 Otis Nixon 59 19.3% 78%
1986 Eric Davis 91 18.7% 88%
1987 Vince Coleman 131 18.7% 83%
1986 Vince Coleman 121 18.1% 88%
1965 Maury Wills 125 17.6% 75%
1980 Rickey Henderson 126 17.5% 79%
1990 Vince Coleman 94 17.4% 82%
1980 Omar Moreno 129 17.3% 74%
1988 Rickey Henderson 106 16.4% 88%
1980 Dave Collins 100 16.3% 79%
1983 Rudy Law 89 16.2% 87%
1991 Vince Coleman 51 16.0% 73%
1990 Eric Yelding 89 15.9% 72%
1988 Vince Coleman 108 15.9% 75%
1981 Rickey Henderson 78 15.8% 72%
1999 Roger Cedeno 83 15.8% 80%
1985 Davey Lopes 51 15.7% 92%
1991 Marquis Grissom 93 15.6% 82%
1976 Billy North 104 15.4% 72%
1984 Dave Collins 74 15.0% 81%
1996 Tom Goodwin 88 15.0% 75%
1986 Rickey Henderson 105 15.0% 83%
1978 Omar Moreno 93 15.0% 76%

Not surprisingly, Rickey Henderson comes out on top, and his 1982 season stands a good chance of never being dethroned as the most aggressive base stealing season in baseball history. And then there’s a whole bunch of years from the 1980s, when the league as a whole attempted a steal every 30 or so trips to the plate. Today’s league average is closer to one steal for every 50 attempts, and with teams valuing outs as baseball’s version of a clock, I don’t see a scenario where we get back to the days of Henderson, Coleman, and the rest.

But keep in mind that the uptick in stolen base attempts at the top end has not come with an offsetting rise in caught stealing rates. The 14 players with 10 or more stolen base attempts so far this year have a combined success rate of 83%. Gordon’s stealing bases at an 86% clip so far, despite a stolen base attempt rate that would rank right between Maury Wills and Vince Coleman. The average success rate for the aggressive runners on the list above was 80%, a few ticks below the success rate for the most aggressive runners in 2014.

This doesn’t mean that today’s runners are better runners, of course. I don’t think it’s a coincidence that league caught stealing rates are declining quickly while offense from catchers is up substantially, as teams have essentially had a two decade run of not needing to care too much about controlling the running game. As the game got bigger and slower, the need for rocket-armed catchers diminished, and it would be perfectly rational for teams to trade out defensive skills for improved offense as stolen base attempts declined.

But if that is the trade-off that the league has consciously made, and we now have a pool of catchers who aren’t being as heavily selected for their ability to stop opposing runners, guys like Gordon and Hamilton are going to have a disproportionate advantage, because they’re the ones who can consistently take advantage of a tenth of a second here or there. At the league level, we’re not going to see massive shifts in stolen base totals — though we are on pace to see about 300 more attempts this year than a year ago — because of the small slice of players who can exploit the change, but for those who can, the advantage could prove significant.

If we set 1994 as the beginning of the era of big offense in baseball, there have only been two seasons since where a runner posted a 15% or higher SBA/PA over a full season: Roger Cedeno in 1999 (15.8%) and Tom Goodwin in 1996 (15.0%). More recently, Rajai Davis and Jose Reyes have put up seasons in the 13% to 14% range, but that’s been the upper limit for a while now. Gordon is unlikely to be able to sustain his current mark, simply because he’s not going to keep getting on base this often, but this isn’t just a Dee Gordon thing.

With less power in baseball, teams are going to look for offense where they can find it, and if the league success rate on stolen bases continues to hang around 75% or even continue to climb higher, base stealing is going to become a viable way of generating real amounts of offense again. We’re not going to go back to the 1980s, but a combination of all these strikeouts and a high success rate on stolen bases could lead us back towards an era of smaller, faster baseball.