Everyone and their brothers have heard the term ERA and for the most part know what it means. But perhaps the novice bettor puts too much stock in that number. This is just more food for thought.
A pitcher’s ERA is reflective of his earned runs allowed, but I think it’s important to look more at HOW those runs were given up and against who. Early in the season, someones ERA might look superb, but if you look at the competition to-date you might find that he’s been on the mound against some fairly weak offenses. The reverse is true in that a starter might have faced the Cubs and the Nationals twice each. So, we have to take that into consideration.
Let’s look beyond that. For me, the next two most relevant numbers are WHIP and fly ball to ground ball ratio. WHIP is the total of walks and hits per inning pitched. It will give you and idea as to how many “opportunities” the pitcher usually gives the other team, in layman’s terms. It also speaks to pitch count and efficiency, both of which can be far more important than ERA. Anything under 1.20 for a WHIP is something that is hard to bet against. That number simply means the pitcher is allowing 1.2 base runners per inning. Anything over 1.40 is generally where we start looking to take the other team, or that pitcher needs to have a great bullpen behind him.
The fly ball to ground ball ratio is important not only because the pitcher with a low frequency of fly ball outs is far more likely to induce a the rally-killing double play. This can also be very good if a pitcher is starting in Coors Field (Colorado) or Great American (Cincinnati), two very small parks.
The reverse is also true and there is no better example of that than Phil Hughes. He was simply crushed in Yankee Stadium with that short porch in right field. But in Minnesota those are nothing but routine outs. It has become almost standard operating procedure to bet against Hughes and the Twins when the are in an American League park that is small and home-run friendly, like Cleveland, Houston, and Texas so know your MLB Ball Park!
The bottom line here is that if ERA is a big factor in you decision-making process, it might be worth digging just a little deeper. That also goes hand-in-hand with something we talked about a while back, which is knowing why your pitcher with a 2.85 ERA allowed six runs in four innings.