Another day, another frustrating performance from Boston's lineup. The Red Sox are starting a crucial stretch of games against subpar competition, and have begun it by scoring one run in two games against the 36-46 Cubs. There's no single guy to blame here, either, which somehow makes it more frustrating. Stephen Drew hasn't gotten going at all since joining the team, A.J. Pierzynski has been inconsistent and mostly brutal to watch, Xander Bogaerts is in the middle of his first extended slump as a professional, and Jackie Bradley has yet to prove he can handle major-league pitching. One more guy who hasn't been entirely himself has been Dustin Pedroia. While the star second baseman hasn't been bad by any stretch of the imagination, he doesn't look like the player he was a few years ago. Is it time to accept that this is who he is going to be for the remainder of his career?
After last night's 3-5 performance, Pedroia bumped his batting line up to .277/.346/.383, good for a slightly above-average 101 wRC+. Much of his performance is similar to how it's been throughout his career. He's walking at roughly the same rate he has throughout his career - right around 10 percent - and his strike out rate remains well below league-average. His batting average is a little lower than where you'd like it to be, with some of that being due to a little less success on balls in play, and some of it partially due to a career-high strikeout rate. The latter part isn't much of a conern, though, since at 12.5 percent it is still a very good rate, and nothing in his plate discipline data suggests it's a looming issue. No, the big concern here is what it's been for over a year now: his power numbers.
Although his three-hit performance yesterday was his third in four games, all of those hits have been singles. Now, his Isolated Power sits at .105, a mark that has him on the same level as guys like Gerrado Parra and Jose Altuve. This isn't a new problem, either, as his ISO last year finished at meager .114. The most common explanation for this power drop off has been injury, as prior to last year he had consistently ISO'd around .160, and could be counted on for 15-20 home runs. With such a quick drop-off in this area, it's any easy conclusion to draw, but it's been long enough where it may not be that simple. That's not to say an injury can't be the problem, but it doesn't look like a situation where Pedroia will quickly heal and get back to his old self. Even if this is a health problem, it looks like one that may be permanent. Other than injury, though, what else could be the issue?
Simply put, the Boston's second baseman hasn't been as successful at driving the ball to all directions. When he was at his best, he was driving doubles and home runs to center and right field on a regular basis. To wit, Pedroia's ISO to right and center field in 2012 was .169 and .109, respectively. In the last two years, though, those numbers have dropped to .103 and .045 in 2013, and .053 and .070. Two years ago, just 31 percent of the now-30-year-old's doubles were hit to left field, but that number has skyrocketed to 57 percent in each of the past two seasons. For a visualization of this phenomenon, see the spray charts displayed below.
As a middle infielder who is officially on the wrong side of 30, this kind of decline shouldn't be that much of a surprise. Baseball players typically get worse at this age, and for Pedroia, it happens to be coming in terms of his power. It's also important to point out that even with this decline in power, he is still a very good player. He still carries a high on-base percentage, and remains one of the elite defensive second baseman in the game. At this moment, he is still clearly an All-Star caliber player. However, that doesn't change the fact that he is starting his decline, and we're probably past the point of waiting for the power to come back. While he's still one of the better middle infielders in all of baseball, it's time to accept that going forward, Dustin Pedroia will be a singles hitter with a high on-base percentage, a stellar glove, and minimal power.