Shelby Miller’s disappearing act

Shelby Miller’s one of the more interesting young pitchers in the National League. In unrelated news, he’s now made three postseason appearances in his career, and the St. Louis Cardinals have lost those three games by 20-3 combined score. Not that you could really blame Miller, who didn’t start any of those games.

Last year, Miller’s relative inaction in October wasn’t a huge surprise. After all, he didn’t debut in the majors until September, and the Cardinals had a stacked pitching staff even without him.

This year, though, Miller started 31 games for the big club. He went 15-9 with a 3.06 ERA. That ERA and his strikeout-to-walk ratio ranked second on the staff, behind only ace Adam Wainwright.

And yet, here Miller is again: watching from the bullpen, with little hope for significant action unless a starter gets knocked out real early or a game goes real late. So what happened? How did Miller get passed on the depth chart by Joe Kelly and Michael Wacha? Here’s the skinny from Bernie Miklasz:

1. Miller isn’t in the rotation for a simple reason: his four-seam fastball backed up late in the season, and wasn’t the same pitch that made him so overpowering for much of the regular season. And if Miller doesn’t have a potent four-seam fastball, he’s vulnerable.

2. The Cardinals have downplayed this, but the organization has concerns over arm fatigue. The team didn’t want to push Miller, who worked a career-high 173 innings this season. Given Miller’s age (he turned 23 Thursday) and developing maturity, it would be stupid and irresponsible to take a risk if the team thinks he was showing signs of wearing down.

And according to data culled from Brooks Baseball, Miller did show signs of wearing down...

There were other signs. He wasn’t throwing his fastball quite as hard in the last month or so of the season. In his last six starts DANGER ARBITRARY ENDPOINTS ALERT DANGER Miller’s strikeout rate dropped from 26 percent to 12 percent. Miller relies on his fastball as much as nearly any other pitcher in the majors; among all ERA title qualifiers, only three pitchers threw a higher percentage of fastballs; there is no Plan B.

If I were the Cardinals, I’d be scared, too.

Still, most teams wouldn’t give up on him. But most teams don’t have the Cardinals’ depth. Considering their options, it’s hardly unreasonable for management to decide that Miller’s not one of their four best starting pitchers. I suppose it’s also worth mentioning that, so far anyway, it’s working out pretty well for them.