ERA is imperfect. This is not news to anyone who has been around baseball for a while. Is it fair when a starting pitcher leaves a runner on 1st base and a reliever comes in and blows up the game by allowing the next 3 batters to reach, including a home run? That runner on 1st base gets attached to the starter. Kind of a rip-off if you ask me.
What about all those low ERA numbers for relievers who you think are horrible? How do they get away with a < 3.0 ERA when they are giving up hits and walks left and right? Sometimes these guys are coming in to the game with runners on base and those hits they give up don't matter, so long as they get out of the inning before the runner THEY let on base scores.
Enter FIP. Fielder Independent Pitching (FIP), takes into account what a pitcher's ERA would look like over a period of time if they experience league average results on balls in play. FIP is based on Ks, walks, hit by pitch, and home runs (not hits). It's based on things that take defense out of the picture. But it doesn't really take into account how many hits a pitcher is giving up. Ie., is the pitcher missing bats or allowing way too much contact? You also have a variation of FIP called xFIP which takes into account ballpark factors in relation to fly balls/homeruns allowed. FIP is a bit more accurate than ERA since it tries to take luck out of the picture.
A newer stat is called SIERA (Skill Interactive ERA). SIERA, unlike FIP, doesn't ignore batted balls in play (which the pitcher has very little control over). SIERA assumes if you are getting balls in play, you are touching more bats. Pitchers who put more ground balls into play, however, generally have a lower BABIP rate since those tend to get outs at a higher rate than fly balls. So with SIERA, strikeouts are good. Ground balls are good. Walks are bad. Fly balls are not very good. SIERA is complicated to calculate. See for yourself. Huston Street, has been on the best relief pitchers the Angels have this year (he should be - he's the closer). His SIERA is 5.55 which is the 3rd highest on the team (behind Javy Guerra and Cory Rasmus). Street has a .152 BAA, .143 BABIP and a 100% LOB rate. However, his FIP is also high and xFIP is 5.65 which may suggest he's getting a bit lucky this year (or perhaps he is generating a lot of pop-ups which get marked as fly balls). According to FIP and SIERA, defense is saving Street's ass and he's not pitching that well. In essence, SIERA doesn't really answer the runs allowed question, but speaks to how effective a pitcher is by looking at how many Ks, outs on batted balls, low walks, low hits, etc.
All those aside, I'd still like to see inherited runners come into play when ERA is calculated. I mean, all those others stats tell you a LOT about how well a pitcher is doing, but if we are going to keep ERA, why not make it more practical?
Unfortunately there is no readily available stat on "inherited runners in scoring position" vs. "inherited runners not in scoring position". I think that matters. If a reliever comes in and a runner is on first, he should get the blame if that runner scores. In a simplistic formula, I think we get a much more accurate ERA stat if we take all the inherited runners scored and give .5 ER for each of those runners to the reliever. Below is what that looks like for the Angels relief pitchers this year. (note that our relievers starting ERAs are not that good to begin with)
The names at the top of this table should be no surprise to those of us who watch the games on a regular basis. If you want to blow up a game with runners on base, you put in Mahle, Alvarez, and Javy Guerra. The rest of the team doesn't look so hot either. In fact, the Angels have allowed 38% of inherited runners to score this year. The league average is 30% and only one team is worse than the Angels this year (the Tigers at 39%). For reference, Oakland and Houston have the lowest rates at 18% and 19%, respectively.
Other stats that stand out in this table (and from other analysis):
- 1.80 ERA for Cam Bedrosian. Is he pitching that well?? Bedrosian actually let's 52% of inherited runners score which is horrible (and second only to Greg Mahle). He's good when he starts clean innings, but not so good with runners on base. Surprisingly, he is showing some really good trends. His ground ball rate is high (which generates more outs), fly ball rate is low (less potential for homeruns, etc.), K rate is high, and walk rate is low. In regards to overall performance, he's doing a lot of the right things which is why his SIERA is among the lowest. With date like this, I'd say you never put Cam in to pitch with runners on. He just isn't good in those situations.
- Like Bedrosian, Deolis Guerra is doing a lot of things right. He's only pitched 8.1 innings, but has not allowed a walk, has a VERY high ground ball rate, and a 10.8 K/9 rate. His FIP, WHIP, and SIERA are the lowest on the team because he is pitching effectively.
- Joe Smith and Huston Street will rarely allow inherited runners to score, but that's because they rarely pitch when it's not to start a clean inning.
- Fernando Salas is not as bad as he looks. He has a very low WHIP, a decent K rate, and a relatively low fly ball rate. His ERA is bad because of the game he pitched on June 4th when he let in 4 earned runs. His ERA drops to 2.40 if you take that game out of the picture. Salas has pitched in 26 games and allowed zero runs in 19 of them. Not elite, but not as bad as he appears. There are worse relievers on this team.
- Jose Alvarez should have been DFA's with Mahle, and maybe Javy Guerra not far behind him. Alvarez has a fairly low walk rate, but his BAA is .310. He's not fooling a lot of hitters and not missing enough bats. Javy Guerra is missing bats, but mostly because he is missing the plate. If you want a guy to come in an walk a bunch of guys, he is your man. He's walked 7 batters in 6.1 IP. His K rate isn't that great either.
- This table is assorted by adjERA from highest to lowest. You will also see a trend that the WHIP generally goes from highest to lowest as well. When you are putting people lots of people on base, you are gonna give up runs eventually. Duh :) The four lowest ERAs on the team below to pitchers whose WHIP is 1.22 or less.