Please click here for the full introduction/primer to this series.

The Semien Report is an experimental effort to provide advanced fielding splits. Every week, I’m going to pull UZR, DRS, and DEF from Fangraphs for each fielder with at least 10 IP at each position on the season. From there, I’ll compare those statistics to the previous week, and in time their numbers from four weeks prior, in an effort to find out who seems to be changing their course, defensively. There are, of course, some caveats:

• I’m not going to bother with pitcher and catcher. Pitcher because it’s already a small sample size I don’t want to parse anymore, and catcher just isn’t evaluated very well by these statistics.
• Advanced fielding metrics take a long time to start to mean anything, so take this with a whole salt lick. It’s very likely that any changes seen for the first few months are just noise, but it’s possible there’s something meaningful there.
• Because I’m breaking down by position, I’ll miss out on utility guys or multi-position wonders. I’m not sure if there’s a great way around this.

In week 7, the “Last Month Split” is very slowly starting to distinguish itself from just being a mini-version of season stats as a whole.  I’ve been having trouble getting the Google Doc to keep my coloring right while adding data every week, so some players have blank coloring after week 7.  This will be remedied.

If you’d like to view the data for yourself, please click here.

So, first and foremost, Adam Eaton had a bad week. This is surprising, as he’s led the world in every category every single week, so far. He lost a point in DRS and UZR, leading to a -1.4 drop in DEF. Looking at his month data, it paints an interesting picture. He looks like he had an insane first few weeks, but has tailed off since then; just 6 of his 14 DRS have come in the last 4 weeks, along with just 3.2 of his 11.3 UZR. This small drop has also allowed the rise of a new leader in DEF this season; Blue Jays center fielder Kevin Pillar. Adam Eaton still has the highest marks in DRS and UZR, but Pillar’s positional adjustment puts him just over Eaton when ranking all fielders. It’ll be interesting to watch and see how this race develops.

Speaking of great players having bad weeks, Nolan Arenado put up his first red row this year. The normally sure-handed hot corner man had a rough go of it, dropping about a point in all three categories. He’s still the best third baseman in the league, but Adrian Beltre is gaining on him, with five others very close behind. Matt Duffy joins both of them in the 7 DRS club, though nobody else has more than 4. Third Base, in general, has a lot of very solid defenders, without any elite ones at the moment.

There are plenty of miserable ones, though. David Wright is still really bad, but he actually had a passable week by DRS, gaining two points and pulling him out of the cellar. The worst defender in the league at the position is probably Danny Valencia or Nick Castellanos now. These guys aren’t known to be bad, but they’re pretty terrible so far, with -8 DRS. Eugenio Suarez pulls up the rear in UZR, though.

Another benefactor of Eaton’s bad week was Giants shortstop Brandon Crawford. Crawford continues to put up elite numbers, and now holds the second spot in DEF thanks to an 8 UZR and a big positional adjustment. His 10 DRS also matches Pillar. By UZR, he’s blowing away the rest of the field with how good he is. DRS thinks he’s the best, but also thinks that Nick Ahmed and Andrelton Simmons (whenever he comes back) could challenge that.

Carlos Correa continues to claw his way back, but it’s slow going. He had a decent week, but not enough to pull him out of the bottom spot in my rankings. If you think that’s a product of having lots of games played, Jed Lowrie is here to disprove that, as he remains the league worst second baseman while on the disabled list.

While I’m on shortstops, Marcus Semien had a bad week, but remains an average-good fielder on the year. Keep it up!

Can I talk about how much I love Adam Duvall? He was always a guy I thought should get a shot on a bad team, and he’s getting that. He could stand to take a walk or two, but for a guy who was mostly thought of as a first baseman, he’s really doing well out there in left. His 8 DRS is only short of Melvin Upton Jr. His 5 UZR at the position is the best mark, though his DEF loses to Kiké Hernandez. Ryan Braun remains a mystery; 3 DRS, -5.6 UZR.

Trayce Thompson needs to take a look at his brother for defense tips; he’s down with Joey Rickard as among the worst defenders in the game. How strange it is that the Dodgers might have both the best, and worst, left fielders in the game. For what it’s worth, Carl Crawford, the man actually listed as their left fielder in the depth chart, is decidedly mediocre. That seems appropriate.

First Base is so weird. The three categories each have separate leaders. Paul Goldschmidt is way ahead of everyone at 6 DRS (2nd place is 3), Miguel Cabrera is the UZR leader with 3.7, and Travis Shaw has the best DEF with 1.6. With all that info, the best fielder at the position, overall, is Joe Mauer. Mauer ranks second in DRS and and UZR, and third in DEF. Eric Hosmer and Mike Napoli are the worst basemen.

Finally, I’ll just conclude by saying the following people are really bad at very difficult positions; they should be moved. Coco Crisp, Tyler Naquin, Brad Miller, and Daniel Murphy. Adam Jones almost made that list due to his -7 DRS, but I just really don’t want to be the one to say “move Adam Jones away from center” because it just feels icky.