Dewan has long known “errors” were an insufficient defensive barometer, but he also thought other companies, including his old company Stats, weren’t even getting the more nuanced details right. Dewan has each of his scouts note not only where the ball was hit but also its type (grounder, fly ball, line drive, or “fliner”) and an estimate of its speed (on a scale of “slow” to “hard”). He says he has quantified the exact lengths of time a ball that is hit to the gaps between the center-fielder and the right- and left-fielders needs to be in the air so that almost every outfielder will catch it (six seconds) and so that almost none will (three seconds). The goal is to figure out what balls certain players get to and others don’t. A fly ball hit to center in Citi Field might look something like this:
Vector 187 degrees. 290 feet.
At the end of the season, Dewan has a complete log of every fliner hit in the major leagues to each of roughly 3,000 zones. He can see which center-fielders caught the most and which caught the least. And using that information for every tiny zone of the field, he can tell you how every player in baseball plays his position relative to everyone else. It’s an extremely structured method of collating subjective judgments. Dewan and company published their results in a 2009 book called The Fielding Bible: Vol. II, which features two proprietary statistics: Plus/Minus and Runs Saved. Plus/Minus is the exact number, tabulated on a play-by-play basis, of plays a defender makes above or below the league average fielder at that position. Thus, at shortstop, Jack Wilson has a Plus/Minus of +32: He made 32 more plays than the average shortstop. That’s transposed into the Runs Saved number, which is the number of actual runs prevented by the fielder; for Wilson, it’s 27, the best in the game at his position. (The process of converting Plus/Minus to Runs Saved is too complicated to explain here, but it’s laid out in Dewan’s book in not-incomprehensible language.) And though no one will confirm it on the record, it is widely believed that Plus/Minus and Runs Saved—thanks to Dewan’s professional connection to Bill James, who now works for the Red Sox—served as the foundation of the Sox’ off-season moves.
The major free-agent acquisitions of everyday players by the Red Sox were not particularly major, at least by the nuclear terms to which we have grown accustomed. The Sox added third-baseman Adrian Beltre, shortstop Marco Scutaro, and center-fielder Mike Cameron. If you’ve heard of all three of them, you’re probably a pretty big baseball fan. None is a regular All-Star or a major offensive force: Beltre hit only eight homers last season, and Cameron is 37 years old and has hit over .270 only once in his career.
What they do well, though, better than almost anyone else in baseball, is play defense. In 2009, Beltre made 26 more plays than the average third-baseman, saving 21 runs, good for third best in baseball at the hot corner. Last year’s primary Sox third-baseman, Mike Lowell, made 23 fewer plays than the average, costing his team eighteen runs. Right there, at one position, that’s a 49-play-above-average improvement, with 39 more runs saved. The generally accepted sabermetric formula is that ten runs saved (with the glove) or created (with the bat) equals one win. With one position switch, the Red Sox might have made a four-game improvement before Beltre takes a single swing of the bat. You can do the same math in center field: Cameron saved three runs last year with the Brewers, while Jacoby Ellsbury, who is moving from center to left this year, cost his team nine: a twelve-run difference, one win. Ellsbury’s shift to left? As a left-fielder two years ago, he saved his team five runs in only 36 games started; 2009 left-fielder (and new Met) Jason Bay cost the Sox two last year. There’s at least another win right there. At shortstop, Scutaro saved twelve runs for the Blue Jays last year; the Sox’ revolving shortstops cost their team nineteen. Three more wins there. The Red Sox have dramatically improved their team’s chances of catching the Yankees without having to shell out nine-figure, decadelong contracts. “In the old days, and even some people today, you’d look at the Red Sox off-season moves and say, ‘They clearly lost more on offense than they gained on defense,’ ” Dewan says. “Now we’re able to measure it, and tell just how much more they gained.”
The Yankees have the exact same idea about defense. They actually made one huge improvement before last season: Mark Teixeira might have tied for the American League lead in homers last year, but just as crucially, he saved twelve more runs (per Dewan) than the lumbering Jason Giambi, which translates to a full win. This off-season, the team decided not to bid for free-agent left-fielders Bay and Matt Holliday, choosing instead to use Brett Gardner to replace Johnny Damon in left field and acquiring the bargain contract of Curtis Granderson via trade to play center. Damon was one run worse than the average left-fielder on defense last year, while Gardner saved nine runs in his limited time in center. Left field is easier to play than center, so Gardner should be even better there, a vast improvement over Damon. Meanwhile, Granderson will probably be substantially better than the Gardner–Melky Cabrera platoon in center. Overall, the Yankees’ outfield defense should be at least two wins better this year, while on offense Granderson will likely match if not exceed the offensive production lost by the departure of Damon. What’s more, he makes only $9 million a year, which is $7.5 million less than Bay and $8 million less than Holliday. All told, using Gardner and Granderson is a way to keep up the defensive improvements of last year—Dewan says the Yanks improved by 41 runs in 2009, amounting to four wins—without costing anything significant on offense or the bottom line. The Yankees and Sox, baseball’s titans of profligate spending—of $50 million bidding wars for players like Daisuke Matsuzaka—are now locked in an equally intense battle to see who can be more subtly ingenious and fiscally responsible.