Zack Greinke’s recent month long and multi-dozen innings scoreless streak garnered a lot of attention. Many of the articles—some of which you can find here, here, here, and here—tended to focus on description and explanation of the streak. The first trait contextualized the streak and rightly identified it as a rare feat, while the second got into the nuts and bolts of how Greinke was able to keep runners from crossing home plate for so long. The explanatory aspect of these articles all turned to luck as a contributing factor. The emphasis on luck led Jack Moore, writing at The Guardian, to criticize the use of luck as an analytical crutch symptomatic of, at best, momentary anti-intellectualism, or, at worst, laziness. He suggests that analysts cite luck because "being wrong is hard," and it’s a way to avoid acknowledging failure.
But what gets lost in Moore’s discussion is just how much of a role luck plays in baseball. Luck isn’t an "artificial" aspect of baseball or baseball analysis, but an essential reality of the game. It always has been. Perhaps some use "luck" as a crutch to avoid admitting their own analytical missteps, but to say luck doesn't play a role in the outcome of baseball plate appearances, games, or seasons is also incorrect.
Consider BABIP. Batting Average on Balls in Play is a metric that applies to batters and pitchers. As a stripped-down description, we can say that BABIP has the ability to tell us about how lucky or unlucky a player has been. If it’s very high for a batter and very low for a pitcher relative to their career norms, they’ve probably been pretty lucky, and that luck is most likely going to be reflected in their other statistics. If the BABIP is very low for a batter and very high for a pitcher, the obverse is true: they’ve probably been unlucky.
BABIP is a statistic that the type of writers whom Moore cites use to identify luck as an explanation. It’s a "new" statistic for sabermetrically inclined writers. But BABIP is only new in the sense that it’s only recently been given definitional shape and christened with an acronym. Read through old conversations between baseball players and reporters, and you’ll find BABIP as the language of luck. "Took a bad hop." "Hit it right at him." "He’d like that one back." "It all evens out." That’s the material of luck in one aspect of the game. The difference between such seemingly timeless bits of lament and relief and BABIP is that the latter gives the former a name and leads to qualified measurement. What we have learned as sabermetricians over the last generation is that "it evens out" eventually, but that it doesn't even out over the course of a single season. A 162-games sample isn't actually long enough to tell you who is truly the best team.
Moore suggests that removing luck from baseball analysis would lead to an advancement in knowledge because it would mean "we have to admit our priors are wrong or incomplete" and that "our predictions will always be flawed . . . It means opening the mind to other explanations, other conjectures to build off and eventually tear down." On the contrary, removing luck from our analysis of the game would dilute the stories we tell. Luck can’t be analyzed out of baseball any more than second base can be. Moore is correct that deifying projections and calling the rest luck is foolish, but luck is a real part of the game as well. And by definition, we should not be able to forecast luck no matter how wise we become.
Roger Angell’s classic 1971 essay "The Interior Stadium" pinpoints the meaning of luck in baseball. As opposed to a hollow prop used to mask the defects in projecting performance, "luck, indeed, plays an almost predictable part in the game." We know it’s going to be there, but we don’t know exactly how. Angell evoked luck in a towering drive "that just hooks foul at the last moment" and "the half-checked swing that produces a game-winning blooper over second". Zack Greinke’s scoreless streak was these moments patched together and sustained, the predictable unpredictability of which made it so damn fun. "Everyone complains about baseball luck," Angell writes, "but I think it adds something to the game that is nearly essential."
The beauty of luck in baseball is that "priors" and "conjecture" aren't a part of it at all. It gives us something unexpected. And, often refreshingly, it doesn’t have to offer a lesson to teach us anything about baseball. Angell concludes his thoughts on luck by saying that "without it, such a rigorous and unforgiving pastime would be almost too painful to enjoy."
Luck can never be removed from baseball, and we’d be poorer if luck were removed from our analytical vocabulary about the game. But that doesn’t mean that the way writers tend to discuss luck can’t be improved. Addressing luck shouldn’t require quasi-apologetic qualifications—sorry, but we have to talk about the luck component—nor does it benefit from smacking readers with a heavy hand ("Streaks Like Zack Greinke’s Require a Ton of Luck"). Luck has an essential function in baseball. Indeed, it’s a feature.
Eric Garcia McKinley is a contributor to Beyond the Box Score. He writes about the Rockies for Purple Row, where he is also an editor. He's among the Beyond the Box Score staff leaders in posts that don't cite any statistics. You can find him on Twitter @garcia_mckinley.