Pitching and defense killing Tigers

With the season approaching the quarter pole and the Tigers still struggling to come close to the potential most of thought they had, it's time for my first statistical summary of the season. One thing to keep in mind as you go through the tables below is that offense is way down in the American League so far this year. The average runs scored per game is down a half run from last year (4.9 in 2007 versus 4.4 so far this year). Thus, where a team ranks among other teams in the league is more relevant than comparing raw numbers between 2007 and 2008.

The Tigers are second in the league in runs scored per game just as they were in 2007. Where they are lagging is in run prevention - 9th in 2007 and dead last so far in 2008. The fact that their runs allowed per game has increased from 4.9 to 5.5 in a much less offensive environment is very telling. Much has been made about the up and down nature of their offense including five shutouts and some feel as if they could be winning more with a more consistent offense. However, their pythagorean estimate of wins based on runs scored and runs allowed is exactly the same as their actual wins. Thus, run prevention is the big problem much more than an inconsistent offense.

Table 1: Overall

	2007		2008
	#	Rank	#	Rank
Record	88-74	5	16-21	12
R/G	5.5	2	4.8	2
RA/G	4.9	9	5.5	14

Table 2 shows that while their isolated power (SLG-BA) is down a little bit (2nd in ISO in 2007 versus 5th in 2008), their OBP is up (4th in 2007 versus 2nd in 2008). The biggest reason for that is an astonishing increase of one walk per game (2.9 in 2007 versus 3.9 in 2008). They don't rank quite so high in batting average this year (2nd in 2007 versus 4th in 2008) but the walks are making up for it.

Table 2: Offense

	2007		2008
	#	Rank	#	Rank
BA	.287	2	.265	4
BB	2.93	12	3.94	2
K	6.5	7	5.8	8
ISO	.171	2	.152	5
OBP	.345	4	345	2
SLG	.458	2	.417	5
OPS	.802	3	.762	2

Table 3 shows that their pitching is bad as it was last year. Looking at the starter and reliever splits, we can see that starters ERA has dropped from 9th last year to 14th this year (a half run worse than the 13th team). The reliever ERA ranks about the same as in 2007. So, as if we didn't already know, the the starting pitchers are a problem. However, it's important to note that their Fielding Independent Pitching ERA does not rank much lower than last year (11th in 2007 versus 12th in 2008). This indicates that, while the pitching is bad, it's really not much worse than it was in 2007.

Table 3: Pitching

	2007		2008
	#	Rank	#	Rank
FIP	4.73	11	4.67	12
ERA	4.57	9	5.10	14
SP ERA	4.68	9	5.44	14
RP ERA	4.37	11	4.47	10

Fielding is harder to measure but Table 4 illustrates that the Tigers are not doing nearly as well defensively this year and this is likely just as important, or perhaps more more so, in their decline as pitching. They were third in the American League in Defensive Efficiency or DER (% of balls in play converted into outs) in 2007 but have dropped to eighth this year.

Using The Hardball Times plus/minus stat, they ranked 3rd in fielding last year and have dropped to 10th this year. In this system, they break down fielding by looking at types of balls hit (ground ball, fly ball, pop up, line drive) . These stats are explained further in an article by Dave Studeman. This system is denoted +/- in the table.

Looking at Revised Zone Rating (RZR), they were 4th in 2007 and 10th so far this year. Each position on the field has a zone around it and a player's RZR is the proportion of balls hit into his zone which he converts into outs. Team RZR is the proportion of balls hit into all fielding zones which are converted into outs. Balls not hit into any zone are not considered in the calculation. For a further discussion of DER, RZR and other fielding statistics, check out Fielding Stats at The Hardball Times by Dave Studeman.

The chart below also breaks RZR into infield and outfield. The table shows that both their infield and outfield defenses have slipped substantially this year. The infield ranked 6th in 2007 and is now 13th. Similarly, the outfield has gone from 1st to 6th. I should note that the Tigers outfield has made more out of zone plays than most teams so far this year so that might bump their rank up a couple of notches. Still, their overall defense is down quite a bit this year so far.

Table 4: Fielding

	2007		2008
	#	Rank	#	Rank
DER	.705	3	.697	8
+/-	+45	3	-6	10
Overall	.829	4	.820	10
Infield	.781	6	.759	13
Outfield	.898	1	.907	6

In summary, offense has not been a major problem this year. They have been inconsistent and they need to improve in that respect but so far it's not causing them to lose games. At any rate, it's not something I'm worried about. They are hitting for average and power, drawing a ton of walks and not striking out a huge amount. The offense will be fine.

The problem is run prevention and it's not just pitching. Sub-par fielding has also been a big contributor to their slow start. With Cabrera at first, Guillen at third and Sheffield in left, I'm not sure how much they can improve their defense without another positional re-alignment. I also think that the range of Placido Polanco and Edgar Renteria may be declining somewhat. So, while the fielding is a problem, I think our best hope is that their starting pitchers pitch better from this point forward.