Stan Musial's Stance

I made a comment on Twitter yesterday that Julio Lugo was better than Felipe Lopez as a shortstop.  To which Erik Manning replied,

Yeah, but Lugo’s knees are gone.  I think a folding chair has more range, at this point.

One could reasonably conclude Erik thinks Lopez’s defensive antics are no worse than Lugo’s defensive ability at this point.  Hmmm.  I’d better take another look at the data.

Two of the more commonly cited defensive metrics these days are Ultimate Zone Rating (which I get at Fangraphs) and Dewan Plus/Minus (over at Bill James Online).  But don’t take my word for it – here’s the data in a graph.

Pretty stark, right? Lugo for his career has been a better shortstop than Lopez.  In fact, here are some of their career numbers at the position:

• Lopez:  602 games, 4995 innings, UZR -42.3, UZR/150  -11.2.
• Lugo:  1078 games, 9016.2 innings, UZR 7.6, UZR/150  1.2.

It’s not a contest.  However, what you should notice – and what I didn’t fully appreciate until graphing the data – is how much Lugo’s defense at SS has dropped off since the 2007 season.  Concurrently, Lopez’s defense seems to have improved since 2006.  However he’s only played 79 innings at the position since the start of the 2008 season, so I’m not sure how much weight we should put into that trend.  Lopez didn’t play SS at all in 2009, probably because he’s a pretty good second baseman.  Lugo, meanwhile, played 671 innings at short in 2008, 400 in 2009, so I think his numbers can carry some weight.

What to take away from all this?  Statistically, using historical data, Lugo is the better defender.  However, doing some rudimentary trend analysis, it’s clear Lugo’s defense has gotten progressively worse the last 2 seasons.  He may very well have trouble beating out that folding chair for the starting spot, and Lopez’s historically poor defense at the position probably isn’t much worse (if it is worse) than what Lugo would give the team in 2010.

We already know Lopez is a better hitter than Lugo.  If the Cardinals are keeping Lugo around for his glovework at short, they might as well let him go and run Lopez out there as needed.