So far, we’ve concluded that almost the entire problem with the Mariner offense in July was a diminished number of home runs.
We also concluded that Corey Hart and Kendrys Morales getting 10% of the plate appearances and contributing nada was a big part of the issue.
But our analysis also indicates that the estimated projection of homers for the Mariners in July, simply based on applying each hitter’s career home-run-per-fly-ball rate to the number of fly balls hit in the month, dropped sharply without factoring in Hart or Morales at all.
In other words, Hart and Morales could have made up for what would have been a flagging offense anyway. The fact that they didn’t made things worse.
But, again, the offense was flagging anyway — due to a lack of balls hit hard into the air.
For whatever reason, spread among most of the Mariner hitters, between June and July:
- Ground balls went up (teamwide from 43% to 46%)
- Infield flies (weak popups) went up (teamwide from 3.5% to 4.4%)
- Balls hit hard in the air (line drives + fly balls – infield flies) went down a bunch (teamwide from 54% to 49%)
Even the players who weren’t exactly “down” in July (Kyle Seager, 4 HR; Mike Zunino, 5 HR — making up 9 of the 13 that were hit) still had fewer balls hit hard in the air (Zunino went from 73% to 48% and Seager from 72% to 57%).
But Justin Smoak dropped disastrously from 60% to 35% before exiting to Tacoma, and Brad Miller, Logan Morrison and Stefen Romero all declined enough to see the predicted diminishing returns in the home run column.
Why did this happen to several players all at once? Even Robinson Cano had fewer outfield flies and only a lone homer (although his line drives went up). Well, obviously they were all playing in the same parks in the same conditions, and facing the same pitchers, so presumably there were some bad combinations of those elements. Perhaps with a “snowball effect” as guys start pressing or get into bad habits.
And it could just be some random variation. But it was definitely happening, and happening to most of the team.
And then … on top of those fewer balls hit hard in the air, there was bad fortune in terms of home-runs-per-fly-ball.
In other words, we estimated fewer home runs due to fewer balls hit hard in the air, and … the M’s didn’t even hit the estimate.
And that’s how they ended up with only 13 homers for the month.
And only 13 homers for the month is how their runs-per-game dropped below 3.
And runs-per-game dropping below 3 is how you go 11-14 with a team ERA of 2.57.