Ryan Howard is having a bad year. He's still showing some power with 6 HRs, but his .165/.285/.331 line is pretty ugly, and his incredible 51 strikeouts have him on pace for about 240 for the season. There is a limit to how much you can strike out and still be a functional major league player.
Most people think that Howard will bounce back once he "gets it going." I do not. To understand why it is instructive to look at Cleveland DH Travis Hafner.
Until he broke his hand in 2006, Pronk was the American League's best hitter, and he was close to that in 2005 as well. 2007 figured to be just another step in Hafner continuing his dominance, but a funny thing happened. Hafner fell off a cliff. His average dropped 42 points. His OBP dropped 54 points. However, what really killed Hafner is his slugging, which dropped over 208 points accompanied by a 40% drop in his home run total. Curiously, he actually increased his walk rate. Conventional wisdom was that 2007 was just a down year from Pronk and that he would rebound in 2008, but so far 2008 has been even worse than 2007.
In 31 games so far this year, Hafner sports a line of .209/.301/.339 with only 3 HRs.
One of Bill James greatest (and least mathematical) insights was that guys with "old player skills" decline more quickly, and have shorter careers than more athletic players. Athletic players tend to lose speed and agility as they age, but also tend to have an increase in power. However, young players with no speed and lots of power fade away pretty quickly. Hafner is a prototypical "old player skills" player. He has been a strict DH for years, he doesn't run well, and he's big. Hafner's precipitous decline started roughly 18 months ago and has not ceased.
Hafner, born on June 3, 1977, is just over two years older than Ryan Howard.
Howard is also an "old player skills" prototype. He's basically a disaster on defense, he's huge, slow, and hit for power at a young age. It is also likely that he peaked early with his phenomenal age 26 and age 27 seasons.
It's possible that Howard is just in a slump and that he will get it going, but it's quite likely that he has entered the rapid decline phase of a guy with old player skills. The strikeouts indicate some batspeed loss, and the decline in batting average and increase in strikeouts, experienced even in last year's very good season, are also telltale signs of decline.
PECOTA gets plenty of things wrong, but it's career-path methodology is especially good at picking out old player skill guys. Hafner and Howard are almost twins when it comes to their comparables. Both feature Boog Powell, Kent Hrbek, Mo Vaughn, David Ortiz, and Carlos Delgado. Howard's 6th most comparable player is Travis Hafner.
All of these guys saw big declines in short order. Some remained effective after their declines, although not nearly as effective as before. Others were out of baseball in short order. Howard's second most comparable player is also interesting; Cecil Fielder.
Which brings me to the reason for writing this. The Brewers have their own "old player skill" 1st baseman. He's also a disaster on defense, slow, (although not as slow as you might think, and not nearly as slow as either Hafner or Howard), and hits HRs at a young age. Prince is only 24 and should still have 3-4 good years left, but "should" is the operative term. While most players peak around 27, some peak earlier than others, and Prince's 50 HR season may indicate that he is closer to his peak than conventional wisdom would dictate. His comp list? 1. Boog Powell, 2. Kent Hrbek. Both of these players declined very rapidly.
I don't really think that Fielder is in his decline right now. I don't think anyone is over the hill at 24. But it will probably come sooner rather than later, and Brewer fans should keep in mind that while Prince is seemingly a good guy, a positive presence in the community, and a fun player to watch, he could become a very expensive mistake if the team hangs onto him for too long.
With guys like Hafner, Howard, and eventually Fielder, the end comes swiftly. It's almost certainly better to trade them early than it is to pay them millions of dollars late.
