Oh What a Difference an Infield Can Make

With the hometown team having fallen on hard times (again) of late, we need something else to look at and today I'm here to provide that. There's been some talk around the Twins blogosphere lately about J.J. Hardy and how he's having a monster season for the Orioles...basically revisiting what a mistake it was for the Twins to trade him away for practically nothing. I am, of course, in wholehearted agreement with these sentiments, but I want to look at things from a slightly different angle. It's been no secret that for the majority of the season the Twins starting rotation (and bullpen) have struggled and though the rotation is pretty much composed of the exact same pieces, the results have been vastly different. I want to try and see what role infield defense has played in that difference and see if we can draw any conclusions.

First, some numbers.

Here are the ERAs, FIPs and xFIPs for the starting 5 from last year. I've also included their groundball-to-flyball ratio and their HR/FB%. For those not familiar with these metrics, FIP and xFIP attempt to remove variables from the equation that the pitcher cannot control with the goal of giving you an ERA-type number than more accurately states how a given pitcher performed. For example, though Francisco Liriano had a 3.62 ERA last year, his FIP was 2.66 and his xFIP was 2.95, good for 3rd and 2nd in all of baseball respectively. In other words, Liriano's pitching performance as a whole last year was much better than his ERA suggested. For more on FIP and xFIP, click the links.

2010 Pitching Numbers for Twins Starters: (ERA/FIP/xFIP), GB/FB ratio, HR/FB%, BABIP

Francisco Liriano (3.62/2.66/2.95), 1.96 GB/FB, 6.3%, .331
Carl Pavano (3.75/4.02/3.86), 1.66 GB/FB, 10.6%, .281
Scott Baker (4.49/3.96/3.82), 0.85 GB/FB,10.2%, .323
Kevin Slowey (4.45/3.98/4.24), 0.56 GB/FB, 8.2%, .307
Nick Blackburn (5.42/5.07/4.46), 1.57 GB/FB, 13.5%, .305

Numbers for the Twins starting staff in 2010: (4.17/3.91/3.84), 1.28 GB/FB, 9.9%, .299, 3.91 SIERA

2011 Pitching Numbers for Twins Starters: (ERA/FIP/xFIP), GB/FB ratio, HR/FB%, BABIP

Francisco Liriano (5.00/4.53/4.41), 1.45 GB/FB, 10.2%, .286
Carl Pavano (4.71/4.08/4.30), 1.48 GB/FB, 7.8%, .302
Scott Baker (3.21/3.49/3.55) 0.77 GB/FB, 8.9%, .299
Brian Duensing (4.56/4.05/4.00), 1.16 GB/FB, 9.6%, .317
Nick Blackburn (4.36/4.76/4.17), 1.98 GB/FB, 14.3%, .310

Numbers for the Twins starting staff in 2011: (4.30/4.18/4.10), 1.30 GB/FB, 9.7%, .296, 4.14 SIERA

Quick Discussion:
The first thing that jumps out at me with these numbers is just how poorly the starting rotation has pitched in 2011 when compared to the 2010 numbers. Even though the HR/FB% is down this year and the GB/FB ratio is up slightly, all three pitching metrics (ERA, FIP, xFIP) are worse for the staff this year. The second thing that pops out to me is that the staff BABIP (batting average on balls in play) is actually better this year than last. This is probably due to the fact that 4 of the Twins starters this year are ground-ball-heavy pitchers compared to only 3 of the 5 in 2010. More ground-balls equals more outs. The main culprits for these year's poor pitching results are Liriano and Pavano, that much is fairly obvious. Both are having terrible seasons compared to 2010 while the bottom 3/5ths of the rotation is actually performing a little better than last year's 3, 4 and 5 starters.

Now, the fielding numbers.

Quick caveat here, I obviously don't have a complete season's worth of number for this year. As a work around to that I calculated how much of this season has been played so far (72.2%) and for the counting stats, I just made the statistical assumption that the Twins will continue at the pace they've been on.

The Whole Team 2010:
78 errors
.987 Fielding%
+54 DRS (Defensive Runs Saved)
30.7 UZR (Ultimate Zone Rating)
3.2 URZ/150

Middle Infield 2010:
34 errors
.979 Fielding%
+27 DRS
11.1/9.9 UZR/UZR150 for 2B
14.0/13.2 UZR/UZR150 for SS


The Whole Team 2011:
116 errors
.981 Fielding%
-19 DRS
3.1 UZR
-0.4 UZR/150

Middle Infield 2011:
40 errors
.975 Fielding%
-18 DRS
-0.8/-0.5 UZR/UZR150 for 2B so far in 2011
-9.4/-12.0 UZR/UZR150 for SS so far in 2011

The numbers really do speak for themselves. Of particular note is the "Defensive Runs Saved" stat. This stat is like WAR (Wins Above Replacement) for defenders. 0 is "average", anything above is good and a getting better, anything below is bad and getting worse. Last year's middle infield for the Twins had a +27 DRS mark which was Top 5 in MLB, this year's team is pretty much the complete opposite story, not only playing to a negative DRS number, but also playing to negative UZR numbers as well. For a team with so many ground-ball-heavy starting pitchers (4 of 5 starters have a GB/FB ratio north of 1.00)...a strong defensive middle-infield is a must and sadly, we've gotten to see first hand how much of a difference it can make.

To my original premise, as I've gone through this I've come to realize how difficult it would be to isolate the effect of poor middle-infield defense on pitching results. It's easy to see that this year's middle infield has been much worse than last year's, but how that ends up affecting the pitching?...well, that's hard to say. I feel confident in saying the two are correlated, of that I have no doubt, especially when the starting staff is as adept at inducing the ground-ball as this one has been. This is my plea to Bill Smith and the Twins...PLEASE get some middle-infield help this off-season...if you're going to keep the same pitchers, improving the middle-infield defense on this team should be, far and away, priority #1 this off-season.