When the Cardinals traded third baseman Brett Wallace, their top draft pick in 2008, and two other prospects to the A's to acquire outfielder Matt Holliday, one word came up repeatedly: protection. The assertion that a hitter's performance varies depending on who is coming up behind him is a long-standing one within the game. It's also a myth.
Statistical studies dating back nearly 30 years have shown that protection doesn't exist. The most recent and thorough look at protection, published in 2006 in Baseball Prospectus's Baseball Between the Numbers, concluded, "There's no evidence that having a superior batter behind another batter provides the initial batter with better pitches to hit; if it does, those batters see no improvement in performance as a result."
What Holliday can affect is the number of opportunities Albert Pujols gets to hit. With Pujols having the best season of his outstanding career, and no Cardinals batter coming close to his level, the '09 Cardinals were faced with the problem that the 2002--04 Giants never solved. In those years Barry Bonds was so much better than his teammates that opposing managers simply took him out of the game. Bonds shattered the record for intentional walks in '02, with 68 passes, and nearly doubled that number, to 120, two years later. By 2004 Bonds was being intentionally passed in nearly 20% of his plate appearances. With men on base, that figure rose to 40%. And with a runner in scoring position and first base open, it climbed to a ridiculous 70%.
With Ryan Ludwick and Rick Ankiel less productive than a year ago, and Troy Glaus yet to play because of a shoulder injury, Pujols was beginning to see similar treatment. Through Thursday, the last day before the trade, Pujols had already tied his career high in intentional walks with 34 and was on his way to the second-highest season total ever, behind Bonds's record.
Adding Holliday, then, could not only give the Cards an upgrade, both offensively and defensively, on Ankiel in leftfield, but also give the team's best batter more opportunities to swing the bat in important situations. Teams are still going to walk Pujols, but they should do it less often than before. This, not some effect on Pujols's batting average or slugging percentage, will be how Holliday "protects" Pujols. The combination is enough to make the Cards a slight favorite in the tight NL Central race.
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