Process, Outcomes, Patience, and xwOBA

One can look at Oakland’s rotation ERA of 4.68, a mark which is in the bottom half of the league, and think it is a staff comprised entirely of batting practice pitchers. A’s starters have allowed 56 earned runs, the 4th-most in baseball and more than 40 more than Tampa Bay Rays starters. My question is are all earned runs really earned? As far as the box score goes, yes. But as far as how they’re earned, my answer is no.

A hitter’s goal is almost always to drive the ball hard either in a gap or over the fence. Even speedy slap would prefer their batted-balls finds gaps between fielders than head directly toward them. Pitchers, on the other hand, desperately want to avoid hard-contact, or any kind of contact for that matter. But when contact is made it would preferably be soft.

Softly hit batted-balls are less effective for producing offense. And Oakland pitchers are among the best in baseball at producing soft contact, or avoiding hard contact.

Oakland starters allow an average exit velocity of just 87.4 MPH to opposing hitters.

Therefore Oakland pitchers have allowed an expected batting average of .286, the lowest in baseball. And Oakland’s .329 xwOBA is also the lowest.

Overall Oakland pitchers have allowed the second-lowest percentage of barrels, narrowly edged out by Houston.

BaseballSavant.com

What does all this mean? Not anything as far as outcomes are concerned. Oakland starters have still allowed the 4th-most earned runs in the league. As I stated before, I don’t believe these runs are earned the same way as say, Boston’s 67 as Boston has allowed much harder contact.

This data is a reason for optimism, though. Oakland pitchers are doing what they should and are avoiding well-hit balls. They’ve merely been unlucky. And you’ll never guess who has been the unluckiest.

By comparing his actual wOBA with his xwOBA Marco Estrada has indeed been the unluckiest starter, followed by Mike Fiers. Naturally these two have Oakland’s worst ERAs.

I know what you’re thinking. That these metrics don’t matter. And I’d say again, I know. But only as far as the outcomes go. The process remains intact. Oakland’s starters are pitching to their strengths but not all are getting rewarded for it.

For example, Brett Anderson is middle of the pack in terms of exit velocity. But he also allows the lowest launch angle, resulting in 53.3% ground balls. That is a good recipe for success given Oakland’s elite infield defense. Frankie Montas, however, has been the one of the luckiest pitchers on the staff. He doesn’t allow terribly hard contact, but his 13.9 degree launch angle is much closer to the ideal angle for hitters. Montas’ ground ball rate is even higher than Anderson’s, his BABIP is lowest on the team at an even .200 and he’s stranded more than 90% of runners. All of that is with a below-average strikeout rate.

I bring this to your attention because it’s far easier to move to throw guys overboard when things go wrong than it is to seek an explanation and solution.

Oakland’s record is just 11-10, but it should be better and by BaseRuns it is. The offense has supplied plenty of runs, and overall the team has outscored its opponents. The data above gives me confidence that better starting pitching is on the horizon. It’s just that it may take the form of better luck, not a major personal change.