In an effort to find to bring a new angle to the routine nature of season previews, last year New English D ran a season preview series based on the team’s nine most pivotal players. We be called the series “2016 Bellwethers,” broke down the players whose 2016 direction would indicate where the Tigers were heading. Due to a solid response, the series is back for 2017. Keep in mind this is not a series about the most important Tigers, but rather the Tigers with the widest range of possible outcomes. You won’t see Miguel Cabrera featured, for example, because of his steady dominance of the league. Enjoy. | #9: James McCann and Alex Avila | #8: Victor Martinez | #7: Whoever Plays Center Field |#6: Jose Iglesias | #5 Jordan Zimmermann | #4: Daniel Norris | #3: Nick Castellanos | #2: Justin Upton

There is no perfect formula for a list like this. It’s designed to attack the season preview genre from a different angle. Rather than breaking down every player or doing some sort of faux projection, I like the idea of ranking barometers. Obviously, if Miguel Cabrera breaks his leg, the team is in big trouble. Obviously, if Verlander is a terrible, the Tigers are done. But that’s not interesting. There’s no value in that kind of a post because it’s plainly obvious. If the good players aren’t good, that’s bad! And if Andrew Romine has a 175 wRC+, that’s good. I think the interesting thing to consider are the players who could go either way.

That’s why the list has focused on guys like McCann, Norris, Castellanos, and Upton. Anything can happen, but it usually doesn’t. Most of the time the best players will be good and the worst players will be bad, but it’s the guys in the middle who matter a lot. It’s the guys in the middle that make or break the team. And there is no more make or break player on the Tigers, perhaps in the entire American League Central than Michael Fulmer.

Fulmer had a terrific 2016 season. He threw 159 innings and posted an 72 ERA- and 88 FIP-. He was somewhere between very good and great. The Tigers weren’t counting on a Fulmer to be a lynchpin last year but he quickly became the team’s #2 starter. Without him, they would not have been in the race until the final weekend.

But there are questions. The obvious one is how Fulmer responds to the increase in workload and the increase in the intensity of his outings. Not only did he throw more innings than ever, he threw high stakes big league innings for the first time. How his body responds to that will be key. The less obvious question is how the league responds now that they’ve seen him 26 times. In his first 120 innings, he had a 53 ERA- and 81 FIP-. In his last 39 IP, it was 130 ERA- and 109 FIP-. I don’t want to oversell those samples, but Fulmer either got easier to figure out down the stretch or he got tired, or both.

There’s nothing wrong with that. He was 23 and ahead of schedule. Everything Fulmer gave the Tigers last year was gravy, but now they’re counting on him to do it again. If Fulmer doesn’t give the Tigers a 3+ win season, it is very hard to imagine them playing baseball past October 1.

There’s no reason to think Fulmer will struggle, per se. He’s talented and he pitched well last year. This isn’t like McCann who needs to improve at the plate or Zimmermann who may be on the decline. But the Tigers are counting on a young, inexperienced pitcher to do a lot of heavy lifting in 2017 and that’s never a good bet. Pitchers break and pitchers have growing pains. There aren’t warning signs specific to Fulmer, but betting your season on a 24-year-old flamethrower is not the highest percentage play.

Many players on his list could step up and get the Tigers over the hump and into the postseason. Fulmer is the player who was critical in 2016 who I think has the highest potential of taking a step back, for one reason or another. It is as simple as this: The Tigers need Michael Fulmer to be very good and there are lots of things that can go wrong.