Smoltz = Weaver (The Good One)

by
August 19, 2009

Today, the Cardinals signed John Smoltz to occupy the #5 spot in their rotation for the rest of the season, after he officially cleared release waivers and was let go by the Red Sox. With an 8.32 ERA at age 42, it might be easy to say that Smoltz’s eight appearances in Boston signify that he’s done as a major league pitcher.

But the sample was just 40 innings, and anything can happen to practically anyone in 40 innings. For example, here’s Smoltz’s career in Boston compared with Jered Weaver’s last 8 starts for the Angels.

Smoltz: 8 GS, 40 IP, 59 H, 9 BB, 33 K, 8 HR, 8.33 ERA, 4.94 FIP
Weaver: 8 GS, 46 IP, 51 H, 18 BB, 54 K, 10 HR, 6.50 ERA, 4.93 FIP

Over the last couple of months, there’s very little separating how Weaver and Smoltz have pitched. Their FIPs are nearly identical, even if they’ve gotten there slightly different ways. Both of them have been stung by the longball, which has outweighed strong BB/K rates. And neither have deserved results as bad as what they’ve gotten.

For Smoltz, there’s an easy narrative – he’s old, he’s washed up, he can’t pitch anymore. For Weaver, there isn’t an easy explanation for his struggles, so the Angels just keep rolling him out there and expect him to get better. But, for both pitchers, our expectations should be similar going forward.

A bad ERA over 40 innings, driven by a high BABIP and HR/FB rate, does not mean that Smoltz is finished any more than it means that Weaver is finished. And, of course, no one thinks that Jered Weaver is washed up.

Cardinal fans just picked up a pretty good pitcher for the league minimum, thanks to the continued overestimation of the usefulness of ERA. The sooner people realize that it’s an obsolete pitching statistic, the better off baseball will be.





 

Dave is the Managing Editor of FanGraphs.

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James C-B
14 years ago

I expected this post to include something about Smoltz’s performance the first time through the lineup vs. the second and third times (and how he is thus better suited as a reliever or how this is a function of his age or his having recently returned from an injury and we can expect improvement – after all, the Cardinals are using him as a setup man to Franklin). I also thought you might mine some PitchFX data and discover that when he misses with a pitch, he misses out over the plate – thus the high BABIP, HR/FB and LD percentages.

Numbers, even good ones like FIP, don’t always accurately predict things when they are completely stripped of context. Sure 40 IP is a small sample size, but there are other factors informing the bad numbers. Maybe Smoltz is just old and tires after 2 IP; maybe he needs more time to recover; maybe his stuff just isn’t good enough to get through the lineup 3 times anymore. Either way, this post is incomplete without even a mention of these factors.

3
sj
14 years ago
Reply to  James C-B

The Sox FO is not dumb and doesn’t overuse ERA.

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Judy
14 years ago
Reply to  sj

It’s such an easy assumption to make, though, isn’t it? Any MLB team does something that isn’t backed by advanced statistical analysis, they must be acting out of ignorance, there’s never any other explanation. Think Cameron really even believes what he wrote?

1
Nick
14 years ago
Reply to  sj

It’s also possible that we (and possibly GM’s) are weighting past performance too much.

In this small of a sample size, neither ERA nor FIP matters too much. Instead, you’d like to get some kind of scouting info. However, the high ERA and ton’s of hits allowed tend to skew peoples impressions of each start.

IOW, what MGL said:

http://www.insidethebook.com/ee/index.php/site/article/sample_size_and_granularity_of_data/

The unbiased form of scouting, like Pitch f/x data, shows that Smoltz’s stuff is still good. His velocity and movement remain at least average on his pitches, and his swinging strike rate and O-Swing are above average, suggesting he’s still fooling hitters.

1
chris
14 years ago
Reply to  James C-B

thanks debbie downer, you’re annoying

0