A.J. Pierzynski has been a very disliked man for a very long time. He has won a number of “Most Hated Player” or “Player You’d Most Like to Bean” polls taken of MLB players, and tends to come across as an irritating guy. Despite all this, Pierzynski is normally respected for his play on the field. The durable catcher has caught at least 125 games over the past 12 years, while slashing a solid .282/.320/.425 over his career (that’s AVG, OBP, and SLG for those who are unfamiliar). None of this track record proved to be enough for the Red Sox, who designated Pierzynski for assignment yesterday after 72 games behind the dish. Pierzynski had been a bust for the Sox at the plate, and his 0.1 Wins Above Replacement meant he contributed very little more than a backup Major Leaguer. What went so wrong for a player who signed an $8 million contract in the winter to be released before the All-Star Break?
We’ll start by looking at how Pierzynski’s last 10 seasons stack up, and this year is not pretty:
Pierzynski has never been great at taking walks (read: he swings at everything), but his decent average has tended to balance that out and help him get on base. This year, Pierzynski’s batting average and on base percentage are both significantly lower than his career norms, and his slugging percentage has seen a large drop, manifesting in just 4 homers. wOBA and wRC+, two statistics that measure overall offensive production, have also seen significant decreases and show that this year he is a below average hitter (average wOBA and wRC+ are around .320 and 100, respectively). Let’s see if we can find the culprit for Pierzynski’s drop in production.
In the first chart, the only real outlier is Pierzynski’s isolated power. As discussed in my last post, ISO measures a hitter’s raw power, and this year Pierzynski has been terrible compared to both his norm and league average (normally around .145). This confirms that Pierzynski’s pop has significantly decreased, as we saw with his SLG and home runs. The batted ball splits also show that Pierzynski is hitting fewer fly balls and more infield flies, indicating he is not getting the barrel of the bat on pitches as much as he used to. And when he does hit fly balls, it is at the worst home run to fly ball rate of his career.
So what does this mean? Clearly, Pierzynski doesn’t have the same pop he used to, and has struggled to square up the ball at his usual rate. Could this be a small sample size of an extended slump that just needs an adjustment, or a sign that father time has finally caught up to Pierzynski’s bat speed? Either way, the Red Sox did not feel it was worth keeping Pierzynski around on a team likely missing the playoffs with promising prospect Christian Vazquez waiting in the wings. Pierzynski will inevitably sign with a team before long, and what he does with his new team could determine if his bat is officially in decline.
Scouting, Stats, and Stuff 