The Myth Of The Myth Of The Orioles' Run Differential

Wilson Betemit, J.J. Hardy and Omar Quintanilla of the Baltimore Orioles celebrate after defeating the Cleveland Indians at Progressive Field in Cleveland, Ohio. The Orioles defeated the Indians 4-3. (Photo by Jason Miller/Getty Images)

The Baltimore Orioles have a good record and a bad run differential. This isn't misleading. It's almost never misleading.

Ten, 15 years ago, it wouldn't have been like this. We would've looked at the MLB standings on and thought "well I'll be damned, the Baltimore Orioles currently occupy a playoff spot." And then that would've been it. We would've been surprised, and we would've committed to paying a little more attention to the Orioles down the stretch.

Now we can't help but look a few columns over to the right. There are the Orioles, at 51-44, tied with the Athletics and barely behind the Angels. But the Orioles are also bearing that big ugly red -44. That's the Orioles' run differential to date, and it's by far the worst in the division. It would also be the worst in the AL West. The Orioles' run differential is 31 worse than the Mariners' run differential, and the Mariners are 42-55. Now we notice the run differential, and now it helps to explain the Orioles' record. "Oh," most think, "it's an unsustainable fluke, then." Of course!

Look at the Orioles' record and you're surprised. Look at the Orioles' run differential and you're left waiting for them to drop out of the race and slip below, where your brain thinks they belong. Enter Ken Rosenthal, who's come to the Orioles' defense, or who's talked to people who've come to the Orioles' defense. In his latest column:

Some sabermetricians view that [run differential] statistic as evidence that the Orioles will falter, but club officials see it differently. In their view, the Orioles' run differential is easily explained.

First, the team's inconsistent starting pitching produces an unusual number of blowouts. A mere seven games - two 12-run losses, one 11-run loss and four seven-run losses - account for a whopping minus-63.

The Orioles' terrific bullpen, on the other hand, enables the club to win an inordinate number of close games - the O's are 10-2 in extra innings and 19-6 in one-run outcomes.

This section of Rosenthal's column is titled "The Myth Of Run Differential." That's always a dangerous stance, because more often than not, run differential catches up with those who think they can defy it. But perhaps we shouldn't be surprised by the response that Rosenthal got, because he talked to Orioles club officials. Of course they'd defend the team that they've built to the media because the alternative would cause a stir.

Let's forget about run differential for a moment and instead break down the contributing factors. The big ones, obviously, are hitting, pitching, and defense. It's pretty easy to just dismiss the significance of one number that is the end result of a combination of several inputs. It's much more difficult to dismiss the significance of the inputs.

The Orioles' starting pitching gets a lot of the blame for the team's negative run differential. However, according to FanGraphs, the Orioles have had the second-worst team offense in the American League, between the A's and the Mariners. That is after adjusting for park. The addition of Jim Thome does help, but it helps only a little bit.

By defense-independent statistics, the Orioles have had the fifth- or sixth-worst starting rotation in the American League. Their 4.41 FIP ranks between the Indians and the Red Sox. They've also had a lower-half bullpen, with a 4.00 FIP that's better than the Angels but worse than the Indians. The gap between the Orioles' bullpen ERA and bullpen FIP is 0.91. The league-average gap is 0.36. There's regression to be expected.

And finally, to finish it off, the Orioles presently have the American League's worst UZR, which is a measure of team defense. They're also the worst in the American League in Defensive Runs Saved, and while there's plenty of room to quibble, usually the differences aren't such that a team said to be really bad is actually all right or even good. There's not much reason to believe the Orioles have had a decent defense.

The Orioles have a strongly negative run differential, and valid reasons have been presented for why they've managed to best their expected record. Those reasons, however, are not sustainable going forward, because this Orioles team doesn't seem to have a strength. The Reds have had baseball's best bullpen, and they're 17-16 in one-run games. The Pirates and A's have the next-lowest bullpen ERAs, and while they've been good in one-run games, they haven't been Orioles-good. And of course, the Orioles' bullpen probably isn't as good as its ERA.

The Orioles' run differential isn't lying. No team's run differential entirely captures what that team will be going forward, and the Orioles have Thome now. Nick Markakis is back from injury. Chris Tillman might be something other than what he's been in the past. There are reasons to believe the Orioles are better than their run differential, but are they that much better? Good teams usually don't have negative run differentials. Good teams usually don't have even run differentials. Good teams usually have positive run differentials, and the Orioles are a ways away from that. Because the factors contributing to the run differential have not been strengths.

Here's the good news for the Orioles and their fans: this is no longer a 162-game season. This is, for the Orioles, a 67-game season, and all kinds of crazy things can happen over small samples. Players and teams can over-perform. The key when you're an underdog team like the Orioles is to hang around and effectively shrink the season, and that's what they've done. They don't have to be better than a bunch of other teams over a full year; they have to be as good or better over several weeks. The probability is more favorable.

And beyond that, the neat thing about the season is that teams can change during it. Just because the Orioles haven't had a fantastic team to date doesn't mean they couldn't add value from the market. I do not think it would be wise for the Orioles to trade any of their top prospects, and the Orioles' front office surely agrees, but that doesn't mean the Orioles can't trade for help. Help isn't always that expensive, especially when you aren't picky about it, and the Orioles aren't in a situation where they need to be picky.

There is no "myth" here. The Baltimore Orioles without question have a better record than they should based on their performance. The expectation is that they'll fade before the playoffs, and that's perfectly justifiable. But what also matters is that the Orioles are still in the hunt, and when a team is in the hunt at the end of July, you can never dismiss the possibility that it'll remain in the hunt until the very end. There's no such thing as retroactive regression. The Orioles aren't going to give any wins back. All they have to do is win games from now on, and that's easier over two months than six months.

Surprise! The Baltimore Orioles are still a total underdog. They're a total underdog that now we have no choice but to take seriously. It is that simple, and there's no universal law requiring that the Orioles start regressing tomorrow. All they have to do is win, what, 35 or 36 of their remaining games? It's the end of July and the dream's still alive, which is enough, for now.

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