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On Wednesday the St. Louis Cardinals signed Matt Belisle to a one-year contract worth a guaranteed $3.5 million dollars. With appearance incentives, Belisle could make as much as $4 million in 2015 salary. The reaction from Cardinals fans to the signing has been decidedly mixed, and that has surprised me a bit. It seems that whether one dislikes the Belisle signing depends on two things: (1) what one thinks of Defense Independent Pitching Statistics (DIPs), and (2) how much one thinks Coors Field hurts pitchers.
Back at the turn of the century, Voros McCracken had a theory that Earned Run Average (ERA) wasn't the best way to assess a pitcher. The notion is that a pitcher's defense has an impact on how many runs cross the plate while he is on the mound and that this is even more true in regards to earned runs, which the official scorer's judgment also impacts. In an article published at Baseball Prospectus, McCracken explained that he sorted pitching stats into two categories:
1. Fielding Dependent:
- "Wins"
- "Losses"
- Innings Pitched
- Earned Runs
- Hits Allowed
- Sacrifice Hits
- Sacrifice Flies
2. Fielding Independent:
- Walks
- Strikeouts
- Home Runs
- Hit Batsmen
- Intentional Walks
McCracken ran the numbers, as explained in his BP article, and reached the following conclusion:
The critical thing to understand is that major-league pitchers don't appear to have the ability to prevent hits on balls in play. There are many possible reasons why this is the case, and I don't really have a concrete idea as to why it is.
But the one thing I do know is that it is the case.
Since then, the notion of DIPs has evolved. It's now generally accepted that pitchers don't have control per se over whether they prevent a hit on a ball in play, but they do have a skill at inducing certain types of contact (e.g., grounders via the sinker) and quality of contact. Nonetheless, a pitcher's Batting Average on Balls In Play (BABIP) is still extremely volatile—which supports McCracken's conclusion.
Perhaps the most widely used DIPs metric is Fielding Independent Pitching (FIP), which is found at Fangraphs. Per the Fangraphs glossary:
FIP is a measurement of a pitcher’s performance that strips out the role of defense, luck, and sequencing, making it a more stable indicator of how a pitcher actually performed over a given period of time than a runs allowed based statistic that would be highly dependent on the quality of defense played behind him, for example. Certain pitchers have shown an ability to consistently post lower ERAs than their FIP suggests, but overall FIP captures most pitchers’ true performance quite well.
By "true performance," Fangraphs means those stats over which a pitcher has almost exclusive control. FIP is calculated based on the following: strikeouts, walks, hit batsmen, and innings pitched. There is also a constant (usually around 3.10), which places FIP on the ERA scale and makes it easier to use for long-time baseball fans like you and me who grew up checking the backs of baseball cards for a pitcher's ERA. Here's the formula used to calculate FIP:
(( 13 x HR ) + ( 3 x ( BB + HBP)) - ( 2 x K )) / IP + Constant
Studies have consistently shown that a pitcher's FIP better predicts his ERA than ERA does. For example, if a pitcher posted a 2.00 ERA and 4.00 FIP in 2014, he would be more likely to have an ERA of approximately 4.00 in 2015 than around 2.00. This is why I tend to use FIP to evaluate a pitcher—especially relievers.
ERA is volatile for all pitchers, but it's particularly up and down for relievers. The reason for this is simple: the number of innings pitched. Most relievers throw between 60 and 90 innings in a season. Most starters throw between 150 and 200. So a reliever's full season is the innings-pitched equivalent to a fraction of a starter's full season. This means that a bad outing or series of outings can have a greater impact on a reliever's ERA than a starter's in a given season because he has fewer innings in which his ERA can even out.
Hot Stove
That brings us to Belisle, who has been excellent by FIP in recent years while his ERA has gone up, up, and up. Here are his stats over the last five seasons while pitching in Colorado:
| Year | G | GS | IP | LOB% | K% | BB% | ERA | ERA- | FIP | FIP- | xFIP |
| 2010 | 76 | 0 | 92.0 | 73.8 | 24.9 | 4.4 | 2.93 | 64 | 2.68 | 59 | 2.78 |
| 2011 | 74 | 0 | 72.0 | 70.5 | 19.3 | 4.7 | 3.25 | 74 | 3.07 | 69 | 3.25 |
| 2012 | 80 | 0 | 80.0 | 72.4 | 19.8 | 5.2 | 3.71 | 80 | 2.97 | 65 | 3.33 |
| 2013 | 72 | 0 | 73.0 | 65.4 | 20.6 | 5.0 | 4.32 | 99 | 3.03 | 69 | 2.99 |
| 2014 | 66 | 1 | 64.2 | 67.8 | 15.3 | 6.7 | 4.87 | 114 | 3.74 | 87 | 3.92 |
| Total | 368 | 1 | 381.2 | 70.1 | 20.2 | 5.1 | 3.75 | 84 | 3.06 | 69 | 3.22 |
To look at Belisle's ERA is to see an alarming trend: From 2.93 in 2010, to 3.25 in 2011, to 3.71 in 2012, to 4.32 in 2013, to a unsightly 4.87 last year. That's an ERA moving in the wrong direction. Being humans, our natural tendency is to want to fill in the next blank in continuance of that trend.
But we can't forget that Belisle played his home games in the thin air of the Rocky Mountains, well above sea level at Coors Field. It's a hitter's haven. That's where the so-called minus stats come in. ERA- and FIP- take a player's stat (ERA or FIP), adjust it for his home park, and then scale it so that 100 is league average. Every point below 100 is a percentage point better than average; every point above is a percentage worse than average.
By ERA-, which is park-adjusted to account for the Coors effect, Belisle was well worse than average. On the other hand, by FIP-, he was about as much better than average as his ERA- was worse. That's been a trend. Belisle's fielding-independent pitching has been better than his ERA.
By FIP, Belisle is one of the 42 best relievers who threw 100 or more innings over the last five seasons; using FIP-, he's one of the top 20 bullpenners in MLB. If we up the innings-pitched threshold to 200, Belisle is one of the 23 best relievers in MLB and his FIP- places him 12th. Among relievers who tossed 300 or more innings between 2010 and 2014, Belisle's 3.06 FIP ranks fourth and his 69 FIP- third.
The Cardinals have signed an innings-eating reliever who has been one of the game's best in the area of defense-indepdent metrics—the combination of strikeouts, walks, hit batsmen, and homers allowed. Moving to St. Louis will take Belisle out of Colorado's thin mountain air and put him on the mound with one of the league's better defenses behind him. This ought to cause his ERA to bend downward, toward his FIP. The Cardinals have bet $3.5 million this will be the case in 2015. At one year in length, not only is that a team-friendly deal, the signing might very well wind up one of the steals of the 2014-15 offseason. General manager John Mozeliak and his lieutenants did well to sign Belisle to the contract they did.