Last week, we took a look at how the Rookie of the Year race was playing out in the National League. Now it’s the American League’s turn.

But before we get there, though, we should take a moment to appreciate that we were pretty close to the waiver trade deadline fanfic we got into happening IRL, as it turned out that the Brewers were the team that won the waiver claim on Yasiel Puig and they were working on putting together a package that included Ryan Braun. The hot takes that a trade involving those two players would have produced from the nether regions of the internet would have been a delight. Alas, we’ll have to wait for the offseason and cross our fingers to see if Milwaukee and Los Angeles can make this happen and bring a little more hot take joy into our hearts.

In other MLB-related fanfic we dreamt upon on a week ago, Tim Tebow may not be going to to the Yankees, but at least he’ll be in New York, as he signed a minor league deal with the Mets.

Now, back to the American League rookies. 

As we mentioned in the article about the National League, the only folks who could have possibly (however unlikely) given the cream of the crop (Corey Seager) a run for the money on the honors for top rookie have been dealing with injuries and it looks like a near certainty that Seager will end up with the award. As we mentioned, things would get very interesting if Seager wasn’t around and there wasn’t a clear winner to make decisions easier and, lo and behold, that’s what we have in the American League’s rookie class this year, where there is no rookie playing a full season at an MVP level.

Michael Fulmer (2.5 fWAR) has been having a very nice season for the Tigers and the RHP is one of the reasons that his team is one game back in the Wild Card race and currently has a 45.9% chance of making the playoffs. His 2.77 ERA ranks first in the AL for pitchers with as many innings pitched and, if he had pitched enough innings to qualify, would lead the AL. His 3.79 FIP is 17th among AL pitchers with as many innings and he’s keeping pretty good company on that list.

As an aside, I’ve been using Fangraphs as the default WAR calculator here, for consistency, because that’s what I did with the NL article. It’s not as if using Baseball Reference’s WAR really made a difference, since Seager would still be at the top, spitting down on everyone else. He might not be spitting from quite as high up (unless it’s the other way around because it’s harder to spit on someone from higher up) but you get the idea (and the picture of a bunch of rookies covered in Seager spit, I’m sorry). For Fulmer, though, it’s worth noting that his 4.9 bWAR is substantially higher than his fWAR. We’re not going to hijack this article and turn it into a treatise on the differences between bWAR and fWAR for pitchers (it’s complicated), but it certainly gives arguments for Fulmer a little more weight.

Fulmer leads the pack of rookie pitchers in innings pitched (136.2), which when combined with his other stats, goes a long way to explaining why he has been so valuable in terms of WAR and in terms of keeping his team in the hunt for a playoff spot. Of course, that comes with the caveat that Fulmer has had his innings limited in the second half to keep his workload down and he still leads all rookies. All of this is to say that we aren’t sure what’s going to happen as the season winds down (as if we ever are…).

Fulmer hasn’t been as dominate in the second half as he was in the first. Add into that the fact that he pitched a complete game shutout against the Rangers on August 14 which required a career-high 112 pitches, that he pitched his worse game of the season his following start and that the following two recent starts haven’t been as solid either, and you can see where the concern lies. Fulmer is already over 12 innings past his prior high of 124 innings, so you can see why this, combined with his decline in the second half could raise some issues over his last few starts.

Astros RHP Chris Devenski (2.2 fWAR) comes in second on the fWAR rookie pitcher leaderboard, but comes in third in innings pitched (97). His 2.13 ERA (lowest among AL rookies) and 2.59 FIP have been a godsend for the Astros, who have been able to deploy Devenski in long relief and spot starts over 41 games when their starters haven’t performed as well as expected. With Dallas Keuchel, Collin McHugh and Lance McCullers all struggling with effectiveness, health or both, Devenski’s value to the team can’t be understated.

One thing that is fascinating about Devenski is just how low his home run to fly ball ratio (3.8%) is. If we set the threshold to 90 innings pitched, Devenski leads all MLB, and it’s not even close. Devenski is currently riding an absurdly low HR/FB and we don’t have that stat for his pitching in the minors to compare it to. If we set the threshold at 90 innings again, but this time look back to 2002, when we can first track HR/FB ratio, you can see that Devenski is in 6th place for the lowest ratio in the last twelve years. 

For more details on HR/FB ratio, feel free to check this out, but the moral of the story is that it’s very unlikely that Devenski can continue to give up as many fly balls as he does and continue to keep the ball in the park. While the ability to limit home runs on fly balls is certainly a skill set and not all luck, being able to consistently run out a HR/FB ratio that low would make him a complete and total statistical anomaly. We’ll have to wait and see whether he’s more like Saul Rivera (who is in the number one spot on that list) or in the company the more esteemed folks on that list, but we certainly don’t have enough to go on right now to just assume that it will continue. 

Again, as with Fulmer, we are playing some predictive games about what to expect going forward, as there isn’t a clear cut winner here. Winning the Rookie of the Year as a relief pitcher is significantly easier than winning a Cy Young, but if Fulmer continues to pitch the way he has been, with (again) that crazy HR/FB ratio, and keeps on gobbling up innings for Houston, there’s a compelling case to be made, especially in the event that Fulmer’s struggles continue.

In terms of position players, Indians centerfielder Tyler Naquin (2.0 fWAR) is one of the possible recipient. His .303/.361/.557 line over 96 games has earned him a 141 wRC+ and made him a very useful hitter for the Indians. That comes with a couple of big caveats though. First, Naquin has been platooned heavily and only about 10% of his at bats have come against LHP. Against lefties, his AVG drops to .222 and his wRC+ drops to 95, which certainly doesn’t help his case. Then there’s another caveat: Naquin’s defense in center has been atrocious. His -17 DRS is the worst among AL centerfielders with as many innings, and his UZR (-6.1) is only slightly better at second worst. Naquin has been a very, very valuable hitter against righties, but his lackluster lefty hitting and poor defense certainly don’t help his case for taking home the award.

Remember how we mentioned earlier that there was no Seager in the AL, a beautiful butterfly emerging from his cocoon in April, fully formed and ready to take flight for a full season? We may not have that, but what we do have, however, is a player who came up at the beginning of August, yelled “screw butterflies” and proceeded to hit the cocoon out of the park.

Unless you reside under a baseball-free rock (and why are you here?), you have likely already heard quite a bit about the exploits of Yankees catcher Gary Sanchez (2.3 fWAR) when he got his first extended call up and was the best player in baseball for a couple of weeks. Thanks to an incredible and historic streak in August, Sanchez was the fastest player in MLB history to 11 home runs and was the first rookie ever to win back-to-back Player of the Week awards. All in all, he hit .389/.458/.832 in August, all while playing solid defense at the most premium position. 

Which brings us to where we are now, where Sanchez leads AL rookies in fWAR despite having only played in 30 games. Obviously, it would be ridiculous to expect Sanchez to put up numbers like that over 162 games. Pitchers are going to adjust to young hitters who break out and it looks they might already have with Sanchez, as he has dropped to .188/.316/.188 line and a 48 wRC+ in September. To be fair to Sanchez, we are talking about a sample size of five games, but he hasn’t hit a homerun in his last 9 games and he is striking out a lot more since he stopped hitting all those dingers.

The correct answer is that Sanchez’s path is probably somewhere in between his hot streak and how he’s hit since since September rolled around. If Sanchez wants to have a serious shot at winning Rookie of the Year, though, he’s definitely going to need adjust back to the pitchers and do it quickly, as he’s got a serious deficit of games to work with as compared to the other Rookie of the Year front runners.

There are certainly some other players having great rookie seasons. Infielder Alex Bregman has been very good for the Astros since he was called up and has hit .262/.317/.470 overall. The best part for Houston is that he started out so cold at the plate (.183/.244/.280 in his first 20 games) but looks to be adjusting just fine to major league pitching after that (.337/.387/.651 in games 21 through 40). Unfortunately for Bregman, the Astros didn’t call him up sooner so, so he suffers from the same issues as Sanchez but without the ridiculous, history making streak to go along with it. There are other relievers who have been generally excellent (Edwin Diaz and his ridiculous 16 K/9 and Joseph Biagini and his 186 ERA+), but Devenski has been better over more innings, so he gets the nod in that category. No other rookie starter holds a candle to what Fulmer has done in terms of quality and innings pitched, so, again, he gets the nod.

In terms of the player who will actually end up winning the award, though, it’s still not clear. If the season ended today, you could make an argument for any of the member of the Fulmer/Devinski/Naquin/Sanchez quartet. I would like to go with Devinski personally, but that’s partially just my preference for the craziness of that HR/FB stat combined with the fact that his stats are excellent overall and the fact I hail from Houston originally. Fulmer might be the most deserving recipient based on how well he has pitched over a larger sample size and the value he’s provided his team. Of course, Sanchez basically dingered the Yankees back into the Wild Card hunt after they sold at the deadline, even if he’s only played about a month’s worth of games. Then again, Naquin has proven he’s not a fluke as a hitter, even if he can’t hit lefties or field or…

I don’t know.  It’s a tough call at this point. Thankfully, we’ve still got a little less than a month of baseball left for somebody to settle things down a bit, so we’ll just have to see who regresses or progresses and leave it to the four players we discussed to sort it out amongst themselves.