Placido Polanco versus David Bell

Last week I argued that Placido Polanco, not David Bell should play third base for the Phillies. Last night I got my wish: Placido Polanco played third base against the Nationals, with David Bell on the bench. Then Phillies manager Charlie Manuel goes and insists that "David Bell is my third baseman."

Bad decision, Charlie. First of all, it'll make you look like a jerk if you do decide to make Polanco your everyday third baseman, since Bell will argue, with some merit, that you've abandoned him.

But more importantly, it's just a bad idea to play David Bell instead of Placido Polanco at third base. The manager's responsible for putting the best possible team on the field. When David Bell's starting at 3B, that's just not happening. Simply put, Placido Polanco is a better third baseman than David Bell.

I offered some brief evidence for this last week, but I'm going to go into more detail now.

First, a comparison of how their offensive contributions this year. Polanco's batting .268, with an on-base percentage of .349 and a slugging percentage of .304. Bell's AVG is .221 (.221!), his OBP is .277 and his SLG is .338. How about OPS (on-base percentage plus slugging percentage) which correlates better with scoring runs than any of those stats individually? Polanco - .653, Bell - .615. Then there's Gross Productive Average, GPA, which more accurately reflects the relative importance of OBP and SLG. Polanco - .233, Bell - .209. The conclusion here is obvious: in 2005, Placido Polanco has made a greater offensive contribution than David Bell.

Now, to be honest, I'm leery of putting too much faith in these numbers. 22 games is an awfully small sample size. So let's look at the long-term numbers.

Placido Polanco's career OPS is .748, David Bell's is .720. OPS+, a stat that takes into account park factors, also has Polanco on top: 95 versus 88. Over the course of their careers, Polanco has simply been a better hitter than Bell.

The there's the fact that Bell is 32 years old, three years older than Polanco. Baseball players' offensive skills typically start declining (sometimes rapidly) after the age of 30. Polanco should be in the prime of his career, Bell is likely on the decline.

Predicting baseball statistics is tough to do well, and I don't claim to be an expert. But it's hard to look at the numbers and not come to the conclusion that Placido Polanco's going to be a better hitter than David Bell this season.

So much for offense. How about fielding? Well, for one thing, fielding ability is notoriously difficult to measure. There's also the problem that there's not much recent data on Polanco as a third baseman, since he was the Phillies everyday second baseman through last season. So any conclusions reached offered here are necessarily speculative.

Over roughly 2300 innings at 3B, Placido Polanco has posted a fielding percentage of .981 and a Range Factor (which measures how many plays a defender makes per game) of 2.48. Bell's numbers are a bit worse: .956 and .239. When you do some league and park adjustments, Bell seems to come out as a slightly better fielder. This jibes with Michael Berquist's recent observation that David Bell is a better fielder than most people realize. Any defensive superiority over Polanco is, however, slight and potentially mitigated by Bell's age and injury history. In short, it's probably a wash.

So there you have it. Placido Polanco is a better hitter than David Bell, and no worse a fielder. Play Placido Polanco regularly at third baseman and you get Chase Utley's bat in your line-up every day. It's as simple as that.

So, could Charlie Manuel please explain why David Bell remains his third baseman?

(I find most of my stats at Baseball Reference. They don't have stats for the current season, so for that I usually go to ESPN.)