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.

Here in week 5, we have our first instance of 1 month deltas.  This is the difference in DRS (no UZR, remember that didn’t become available until just after my 2nd report/week 3) between the current week and 4 weeks prior.  The goal behind this is to see who’s had the best month.  It’s not entirely useful yet, since week 1 DRS was already really noisy.  I don’t imagine it will be useful at all until at least week 8, when we begin comparing to data samples that were a month into the season.  I may still make some occasional references, though.  If you’d like to view the data for yourself, please click here.  This data was pulled from Fangraphs between 10 PM PDT and 11 PM PDT on Wednesday, 5/11/16.

The Outliers:

Poor Andrelton Simmons finally climbs his way to the top spot in DRS only to get injured. Oh well; this won’t be the last we see of him. Nick Ahmed is right there with him, and hopes to go uncontested next week to claim the throne with 7 DRS. Brandon Crawford still owns the UZR and DEF titles. Meanwhile Carlos Correa continues to be bad, and at this point all the metrics agree; he is a miserably bad shortstop. He’s the worst in the league right now.

Best Week Ever:

Zack Cozart sits alone at +3 DRS this week. His strong week puts him in elite company; he’s a top 5 shortstop in the game now by DRS at +5 on the year. UZR is hard to come by, but it’s a bit easier for those stuck in the muck and mire, and that’s where we find Trevor Story. The youngster is trying to turn his success at the plate to use in the field, and improved by 1.8 UZR this week. He’s still in the bottom 10 on the year, but this is a nice improvement.

Worst Week Ever:

I really don’t understand how Carlos Correa could be this bad. He’s been a bottom 3 shortstop every week so far, and he tops the charts again at -3 on the week in DRS. He’s an appalling -9 in the season; the worst around and he’s beginning to run away with the title. He also topped the UZR leaderboard with -2.1 to put him at -6.7 UZR on the year.

Semien Special:

Marcus Semien had a relatively strong week, and now sits back on the right side of league-average again. Great work buddy.

Checking in on the ROTY Race:

Corey Seager isn’t much to look at by DRS with just -1, but UZR thinks he’s a more than capable defender with 2.9 UZR, and with the positional average he’s a 4.2 DEF defender. Those are pretty decent credentials so far, kid.

Center Field:

The Outliers:

Kevin Pillar has wrested control of the throne back from Mallex Smith this week. His 8 DRS on the season is uncontested. UZR thinks he’s even better than that; his 7.2 UZR is more than twice the total of the next best defender in center, a resurgent Delino DeShields. Meanwhile, Tyler Naquin continues to dig his own grave. He sits at -7 on the year, inching closer to costing his team an entire win. Denard Span of the Giants is losing the UZR race with -5; his positional adjustment isn’t enough to save him from a disastrous -4.5 on the season in DEF.

Best Week Ever:

It’s actually Leonys Martin who takes the crown for the week. He doubles down on last week’s +2 effort and surges into very strong territory with a +5 on the year in DRS. Fellow southwesterner Chris Owings put up a +2 UZR week in an effort to make his mediocre UZR catch up to his strong DRS campaign. He sits at breakeven in UZR on the year but an excellent +6 DRS.

Worst Week Ever:

Ramon Flores of the Brewers makes his first appearance on the report, unfortunately it’s for the wrong reason. Fat, drunk and -3 DRS is no way to go through a week, son. Last year’s surprise Odubel Herrera also makes his entrance, only to fall on his face and lose 2.7 UZR on the week. Yipes. Both of them are merely unimpressive on the year, though, so there’s plenty of reason to think they’ll turn it around.

Action Jackson:

What was looking like a miserable start to the season for Austin Jackson has turned around. He’s very quietly clawed his way out of the pit back towards breakeven territory. He’s not there yet, but the trend is good.

Second Base:

The Outliers:

We have not just one new champion, but two this week. Ryan Goins and Dustin Pedroia both put up big weeks to sit at +5 DRS on the season. Goins has always been known for his defense, but Pedroia’s resurgence is nice to see as well. Pedroia even manages to win both ends of the crown this week, as he owns a +3 UZR on the season. You’d think he’d start declining at age 32, but I guess not. Unfortunately all is not well in scrappyville, as Kolten Wong, once a very promising padawan in the scrappy Jedi school, is the worst DRS on the year at -4. Jed Lowrie and Jean Segura continue to put up the worst showings by UZR.

Best Week Ever:

Well look at that! It’s Brett Lawrie this week who put up the best week at +3 DRS. His reputation has always been as a promising, though very inconsistent, player, and this only upholds that reputation after poor showings in previous weeks. Jose Altuve gained 1.8 UZR on the week to try and put himself back in plus defense territory. With his absurd offense on the year, though, any contributions with the glove are gravy.

Worst Week Ever:

I don’t feel the need to talk about Jed Lowrie again, so I’ll highlight another on-again-off-again Athletic in current Padre Adam Rosales. His -2 DRS isn’t inspiring, and may buy him a ticket back to AAA real soon. Robinson Cano gave away what little goodwill he had with a -1.6 week, and now sits just above 0 on the year.

Confusing Kipnis:

Jason Kipnis confounds the metrics a bit this year. He’s at -3 DRS but +2.8 UZR, the latter being close to the top spot. Weird!

Third Base:

The Outliers:

Nolan Arenado may have allowed his competitors to gain on him, but his +7 DRS on the year keep his legacy intact. He also improved his UZR quite well, and his +5.8 would be exceptional at any position. On the other hand, we have David Wright, who just continues to scuffle as questions arise about his future. I don’t want to dump on his career other than to say he’s the worst at his position so far this year, and it’s not that close.

Best Week Ever:

It was a relatively boring week for the Hot Corner; Anthony Rendon was the only +2 DRS score this week. He improves on the year but continues to tail the front pack in that category. Much has been made of Javier Baez‘ defense enabling the Cubs lineup in a wholesome way, allowing Kris Bryant to move to left, and UZR backs that up. In 5 games this week he gained 2 UZR, which is big for a guy who has only played 11 games at the position this year. Keep an eye on him.

Worst Week Ever:

There are a few guys tied here, but I’ll happily pile onto the Angels’ catastrophic week by pointing out Yunel Escobar‘s -2 DRS on the week. I feel really bad for him; seriously. Todd Frazier also had that score, but I’ll make more of his -2.3 UZR which puts him on the wrong side of the tracks. It’s fine, though, as the White Sox have plenty to cheer for.


What happened to Josh Donaldson‘s defense? He’s got an elite reputation, but this year the metrics say he’s wholly not worth your time. Maybe his age is starting to creep up on him.

Right Field:

The Outliers:

Adam Eaton somehow continues to improve his torrid pace. He’s now at 14 DRS and 12.2 UZR. For reference, Kevin Kiermaier last season was 42 DRS and 30.0 UZR. I’m not saying he’s on pace, because I don’t know if these metrics work like that, but he’s certainly trying his best. Amazingly, we have a new bottom-of-the-barrel in right field, and it’s Hunter Pence. His -7 DRS on the season may threaten a move to left if not improved, and particularly concerning are his poor arm ratings. Don’t worry Jay Bruce haters, he’s still the worst in UZR at -7.6 Keep fighting, big guy.

Best Week Ever:

Last week was a long time ago. Curtis Granderson put forth a great effort in his climb back to respectability. He added 3 DRS and a decent UZR score to be the most improved right fielder for the week. What remains of Peter Bourjos had a very good week though by UZR, with 2.6 added points. There’s hope for all of us.

Worst Week Ever:

Yeesh. Miguel Sano is putting any doubts to rest as to his DH future. Losing three points of DRS isn’t what we wanted to see here, Miguel Angel. That said, UZR actually thinks he was quite good on the week. It’s David Peralta who had the worst week according to the second metric. He lost -2.1 UZR on the week and continues to bounce around zero.


Josh Reddick is the one splitting the room at the position. DRS loves him at +3, while UZR (and, thus, DEF) think he’s just miserable. At least he’s hitting the ball well.

Left Field:

The Outliers:

We’ll discuss why later, but Melvin Upton Jr. has soared into #1 on the leaderboards. He’s at an absurd +8 DRS on the year, which makes his 0.6 UZR simply confounding. Oh well, let’s celebrate his revival for what it is and not what it isn’t. Adam Duvall continues to be a resounding success for the Reds, and he’s now leapfrogged his way to the top spot in UZR with 4.7. Gerardo Parra continues to waste away with -6 DRS, while our old favorite Joey Rickard continues to languish with -4.9 UZR.

Best Week Ever:

Upton had a huge +4 week to claim the top spot, but Kike Hernandez shares the spotlight with the same score. They’re #1 and #2 on the year as well; it’s a two-man race at this point. Duvall also has to share his weeklong crown, but he splits the seat with Christian Yelich of the Marlins. Yelich simply looks like he had a good week though, unlike the others, who are looking like elite defenders at their position this year.

Worst Week Ever:

Like the Frazier of left field in more ways than one, Melky Cabrera lost 4 DRS on the week. Not a great week for White Sox on the left side of the field. He lost 2.4 UZR this week too, which was the worst such mark. Yikes.

Let’s Just Talk About Cubs:

Kris Bryant has already put up a +2.3 UZR in 16 games while helping shore up a Cubs defense which ranks best in the league. It’s easy to forget how good he is on that team, especially when you consider his flexibility.

First Base:

The Outliers:

Don’t forget: Paul Goldschmidt is really good. He put up a nice week to vault to the top of the DRS leaderboards mostly to remind us of that fact; he’s at +4 on the season. Miguel Cabrera made his triumphant return to third base this week, but he stands as the best first baseman by UZR still at +3.4. It’s Eric Hosmer, Mike Napoli, and Brandon Belt who all have claims on the low-end for first baseman though. They’re all rather uninspiring across the board.

Best Week Ever:

Goldy was #1 over this period. +2 may not look like much, but for a first baseman it’s a decent week. Remember when Mark Reynolds was the worst third baseman in the league? Well now he’s the best (UZR) first baseman for the week. Give that man a gold star.

Worst Week Ever:

Everybody’s bad. The worst, I guess, though was Ryan Zimmerman. In addition to being bad enough with the bat to inspire a million walks for Bryce Harper, he had bad marks across the board for defense, losing the most of any first baseman in both UZR and DRS. Rough.

Votto Blah-to?

Joey Votto has openly discussed how he hates not being great, and his defense isn’t any redemption. He’s always been quite good, but this year he’s just another mediocre guy at the easiest position.

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