Reader Zac Fieroh recently wrote an interesting FanPost in which he analyzed the biggest problem area in the 2015 Detroit Tigers’ bullpen. Determining why a plan failed by identifying the weakest link in the chain can be a valuable exercise, and the post explained that the pitching in the seventh inning was easily the Tigers’ worst problem.

Let’s take that analysis one step further. We have identified the seventh inning as the weak link, but we need to know why it broke before we can determine whether it's fixed. Which pitchers are to blame, and are they still being relied upon in a similar role? What exactly happened in those innings?

Al Alburquerque was Brad Ausmus’ de facto "seventh-inning guy" for most of the season, and he led the team with 87 plate appearances in the seventh. He held hitters to a .650 OPS in the frame, so he wasn’t necessarily part of the problem. The issue must be rooted elsewhere.

Blaine Hardy saw the second-most mound time in the seventh, and got hit to the tune of a .779 OPS in his 63 plate appearances. That’s less than ideal, and Hardy could be pointed to as one reason why the seventh inning was such a struggle.

That's pretty odd, right? Hardy had a good season. His OPS-against in innings other than the seventh was only .682, which is just fine. The .432 BABIP against him during the seventh inning is a big red flag. Hardy’s results were certainly part of the problem, but it’s hard to blame Hardy himself. This looks more like old-fashioned bad luck in a small sample of data.

So Alburquerque was fine, and Hardy got unlucky, let's keep moving. Next on the list is Anibal Sanchez, who got absolutely rocked in his seventh-inning plate appearances. Then David Price, who allowed a very un-Price-like .731 OPS, and Alfredo Simon with a .776 OPS.

Are you starting to notice a pattern? Those guys are all starters. Maybe this bullpen problem isn't really a bullpen problem after all.

PA BA OBP SLG OPS Anibal Sanchez 61 .308 .383 .692 1.076 David Price 58 .298 .310 .421 .731 Alfredo Simon 58 .333 .368 .407 .776 Justin Verlander 50 .340 .380 .404 .784

Nearly half of the Tigers' seventh-inning plate appearances were pitched by one of their veteran starters, a group that was rightfully expected to perform at a higher level than a typical middle innings reliever. Collectively, they allowed a .843 OPS, with Sanchez by far the worst offender.

When you see a phenomenon such as this, it's fair to wonder if there is one flaw in team philosophy rather than four separate flaws in four individuals. Perhaps the coaching staff has a tendency to leave their starter in one inning too long? Consider this snippet from the 2016 Baseball Prospectus Annual.

We noted last year that Ausmus’ Tigers led the majors in blown quality starts. We couldn’t figure out why, though we offered three theories: 1) Ausmus hadn’t adjusted to the pace of the game from the bench; 2) Ausmus figured his bullpen would blow the game anyway; and/ or 3) Ausmus was too darn stubborn to change pitchers. Whatever explanation or combination of explanations applied in 2014 probably worked for 2015 as well, because the Tigers again led the majors in blown quality starts.

Blown Quality Starts measure games in which a starting pitcher has registered a quality start through six innings, but lost it by allowing a fourth run later. The Tigers have led the majors in Blown Quality Starts in each of Ausmus' two seasons as manager. Furthermore, the Tigers' starters threw more total pitches than any other staff in 2014, and ranked fourth in starts of at least 100 pitches in 2015, despite having one of the worst rotations in baseball.

This is a small pile of evidence pointing towards one conclusion: Ausmus has a habit of leaving his starting pitchers in the game too long, and that contributed to a big chunk of the seventh-inning woes last year.

Perhaps they've preferred to stick with their starting pitcher longer than would normally make sense due to their bullpen's resemblance to a conflagration of a large waste receptacle. This argument does hold water, and was presented in the BP Annual over a year ago. But Alburquerque has been the preferred pitcher to relieve the starter over the last two seasons, and he has performed well in the role.

Hopefully better relief options this season will provide Ausmus more reason to pull his starters before they fall apart. Al Avila’s revamped bullpen was desperately needed, but it won’t mean much if the starters are continually allowed to pitch one inning too many.