Why Jake Westbrook suddenly became the St. Louis Cardinals' biggest problem

Kolten Wong is up, Oscar Taveras is injured, Ryan Jackson is slumping, and Pete Kozma is more bulletproof than the hometown guy who single-handedly won the World Series two years ago. Jake Westbrook, then, picked an especially bad time to put together his fourth bad appearance in a row.

If you weren’t watching his peripherals, though, his summitting the Cardinals’ mountain of problems was pretty sudden. When that run of bad starts began, his ERA was 2.95, and he’d delivered 10 quality starts in 14 attempts. He’d also struck out 32 batters and walked 33 in 88 innings.

Last year, Jake Westbrook struck out 5.5 batters per nine innings, his second-best rate ever. Now he’s striking out fewer than three-and-a-half batters per nine innings. That’s the worst rate of anybody who’s pitched more than 100 innings, and were it not for Scott Diamond (of the notoriously strikeout-averse Twins) it would be nearly a strikeout-and-a-half worse than the next lowest qualifier, Bartolo Colon. He’s also the only pitcher who’s topped 100 innings, this year, while walking more batters than he’s struck out.

When your results are outpacing your peripherals things can get rough in a hurry, because you’ve never really looked all that good. Jake Westbrook never looked like he had an ERA under two, and now he doesn’t; now his results, like his peripherals, suggest there’s a problem.

But what helped usher Jake Westbrook to the top of everybody’s list wasn’t just his performance—it’s the performance of the players around him. Jake Westbrook isn’t Jon Jay or David Freese, and the pitchers behind him aren’t Ryan Jackson. They’re Michael Wacha, sitting unconvincingly in the bullpen, and Carlos Martinez.

It’s difficult already to pick Westbrook as the fifth-best starter the Cardinals have—Westbrook who’s been something like an average starter once since coming back from elbow surgery, and whose value is staving off replacement level for six innings a week. This year Westbrook’s had the opposite effect, and so long as Adam Wainwright, Shelby Miller, Lance Lynn, and Joe Kelly are all healthy he’s on the wrong side of the door replacement level is pounding at.

Westbrook’s bad run has already led to theories about why he’s still in the rotation at all, which I’m not sure are necessary—inertia and his solid results until last month probably had a lot to do with it. Michael Wacha’s innings total also seems relevant; I think his move to the bullpen is as much about keeping him from regular work in Memphis as it is bolstering the major league staff. (He’s up to 110 innings between Memphis and St. Louis so far, after pitching 134 between amateur and pro ball last year.)

But the Cardinals are out of slack this year—they can’t afford to push Wacha or Martinez too far, but they also can’t afford to coast and set the board up for next season, unless they’re keen on trying the Wild Card play-in game again. If Jake Westbrook is their fifth-best starter right now, Wacha should probably still be in Memphis.