The Most Improved Defensive Players, As Far as We Can Tell

The Gold Glove Award winners were announced, and you probably noticed. You probably can’t recall off the top of your head all of the winners, but you can recall some of them. To whatever extent people care about awards, my sense is they care relatively little about the Gold Gloves, because the awards have a history of being stupid and because it’s just really hard, still, to measure defense. The Gold Gloves are the, I don’t know, Sporty Spice? of the baseball awards season.

There’s also the part where the Gold Gloves can just confirm what you already know. You have ideas in your head of the year-to-year best defensive players at each position. What gets a lot less attention are defensive improvements. There are reasons for that, but anyway, it’s interesting to know, for example, that Andrew McCutchen was an awesome hitter in 2014, but it’s differently interesting to know that the same could be said of J.D. Martinez. Baseball’s fun when expectations are met. Baseball’s fun when expectations are not met. Baseball’s fun! So let’s dedicate a little time to players who just took a defensive step forward. As much as we can measure that, I mean.

I wanted to ultimately end up with five guys. Five is a good number of guys. Any more than that and you have to take separate cars. I also wanted to compare 2014 performance to 2013 performance, and nothing more. Decisions were made. I set innings minimums of 750 for both seasons. I used the Defense rating based on UZR, I used a defense rating based on DRS, and I used results from the Fan Scouting Report. I measured the year-to-year change in each, in the form of z-scores, such that I wound up with three numbers capturing the change in performance. Then I just averaged the three numbers, therefore weighting UZR, DRS, and the Fan Scouting Report equally. So let’s say a player wound up at 1.0. That would mean, relative to 2013, the player was one standard deviation better in the field in 2014 on average, across the three categories.

Below, the five most improved players, statistically. Also these three runners-up: Alex Avila, Kyle Seager, and Jhonny Peralta. They didn’t miss by much. They did miss.

No. 5

Lucas Duda

  • +1.37 (standard deviations)
Season UZR DRS Positional FSR Innings
2013 -11 -12 -5.2 20 774
2014 0 5 -10.8 37 1228

An allegedly representative play:


Duda wasn’t so much a good defensive player in 2014. It’s more that he stopped being a complete and utter catastrophe. The Mets chose him and stuck with him for his bat, but he very much relished an opportunity to no longer regularly play the outfield. At first, he didn’t embarrass himself, although for the sake of honesty, when I was looking up the play above, I initially fast-forwarded to what turned out to be a Duda error. Now this is where it’s important to understand what’s really being measured. It seems like Duda improved because he played mostly first base instead of mostly corner outfield. His skillset, perhaps, is better suited to an infield corner. So while, by these numbers, Duda was among the most improved defenders, he didn’t improve at his position. He improved mostly by switching positions. That’s going to be the case with a few of these guys. I hope you don’t feel deceived, but I also can’t worry about all of your feelings.

No. 4

Anthony Rendon

  • +1.40 (standard deviations)
Season UZR DRS Positional FSR Innings
2013 0 -11 2 55 840
2014 7 16 2 72 1364

An allegedly representative play:


Duda switched from the outfield to first base. Rendon went from playing mostly second base to playing mostly third base. His numbers were better at both positions in 2014, and the fans fell in love with him. He scored 25 points better on instincts, somehow. First step, 13 points better. Hands, 24 points better. Arm accuracy, 17 points better. Compared to the year before, Rendon committed one more error in 550 more innings. And this is a guy who’s bounced around some, which isn’t an easy thing to pull off. When Rendon was younger, the Nationals had him evaluated as a Gold Glove-caliber third baseman. Add that to his running and his hitting and Rendon’s looking like a regular MVP candidate.

No. 3

Alexi Amarista

  • +1.42 (standard deviations)
Season UZR DRS Positional FSR Innings
2013 -10 -5 1 37 819
2014 4 10 4 48 1084

An allegedly representative play:


I bet you didn’t think you’d be reading about Alexi Amarista at the beginning of the offseason. If it helps, we’re almost to the next guy. The Padres, in 2013, gave Amarista pretty regular time in center field, and it would appear Amarista wasn’t particularly comfortable. He came up mostly as a second baseman, albeit one with versatility, and this past year Amarista played mostly short. He took to it capably, and for good measure, he also held his own in the center-field innings he still picked up. According to the Fan Scouting Report, people have submitted ballots for Alexi Amarista. Give it a chance and the world will surprise you.

No. 2

Mark Reynolds

  • +1.63 (standard deviations)
Season UZR DRS Positional FSR Innings
2013 -5 -11 -6 30 919
2014 12 6 -5 45 943

An allegedly representative play:


Look: I don’t know. The neat thing about this post is I can’t be blamed, because it’s not like I’m making up the numbers. I’m just bringing the data together. According to DRS and UZR, Reynolds was better this past season at first base. According to same, he was better this past season at third base. The fans saw significant improvement across the board. Reynolds turned 31 in August. His career Defense rating is -74. The numbers say, historically, he’s been bad at first and bad at third. This is one of the things we’ve long known about Mark Reynolds, one of his flaws that’s gone almost without saying. So what do you make of the year that just happened? If Reynolds struggled in the field again, we’re not in possession of the evidence. At the end of the day, I’m just the messenger. Believe in this, or don’t. The Brewers were winning games somehow.

No. 1

Daniel Nava

  • +1.77 (standard deviations)
Season UZR DRS Positional FSR Innings
2013 -12 -6 -6 42 1058
2014 13 17 -5 39 838

An allegedly representative play:


And, well, isn’t this interesting? Nava’s four years of Fan Scouting Report results:

  • 2010: 40 overall
  • 2012: 40
  • 2013: 42
  • 2014: 39

That’s consistency. The fans haven’t seen anything. The numbers must’ve seen something. While the FSR results didn’t budge, DRS and UZR combined to more than make up for that and push Nava to the very top slot. He spent the last two years mostly in the outfield corners, and if we believe what the numbers suggest, Nava as a right fielder was amazing. When I was loading up the play above, I initially went to a play where a fly dropped in front of Nava and bounced right by him. Not that one play ever tells a story, but, here we are, finished but wondering. As far as we can tell, in 2014, Daniel Nava was baseball’s most improved defensive player. That’s certainly something, all right.

Jeff made Lookout Landing a thing, but he does not still write there about the Mariners. He does write here, sometimes about the Mariners, but usually not.

Newest Most Voted
Inline Feedbacks
View all comments
9 years ago

Rendon is good at everything and he’s starting to become great at a lot of things.

9 years ago
Reply to  David

Yep. Rendon is starting to become great at being good at everything.

9 years ago
Reply to  Yovani

Next he will start to become good t being great at everything. When he becomes great at being great at everything, he will have achieved baseball Nirvana.