The Jay Bruce Defensive Metrics Test

Jay Bruce is going to be traded. That’s a near-certainty. He’s the only player on this year’s market to be (almost) traded not once, but twice by the team for which he still plays. The rumors have been persisting for more than a year now. Bruce is in the last guaranteed year of his contract, the Reds were never in contention, and he’s rebuilt his value with a great first half at the plate. Already, we’ve heard Bruce linked again to the Blue Jays, alongside the Indians, Nationals, Dodgers, and others. It will be an upset if he finishes the season wearing a Cincinnati uniform.

That much about Jay Bruce, we can be confident. We can be confident that he’s been a good hitter in the past, we can be confident that he’s been a good hitter in the present, and we can be confident that he’s likely to be moved within the next month. There exists an area of Bruce’s story that’s far more murky, though, and one’s perception of that area of Bruce’s game goes a long way towards one’s evaluation of Bruce. Despite a 120 wRC+ this season, Bruce has been worth 0.0 WAR, according to our calculations and 0.4 WAR by Baseball-Reference’s, and that’s all due to his defensive numbers.

The defensive numbers hate Jay Bruce this year. Ultimate Zone Rating calls him the season’s worst defensive right fielder, among 21 qualifiers. Defensive Runs Saved has him in a tie for last, with J.D. Martinez. Those negative marks stretch back a couple years now, but then you get recent tweets like this from Jeff Passan:

And quotes like this out of Buster Olney columns:

Bruce’s defensive metrics are not good, but some scouts believe that he’s better than those numbers indicate, and wonder if his skills are properly reflected in the stats — which some evaluators believe may be inexact.

And you begin to sense a divide on the evaluation of Bruce’s defensive ability. And it’s an important divide, because a Bruce with average-to-better defense is a useful player. A Bruce closer to what the defensive metrics suggest is a replacement-level designated hitter. Those two players fetch far different returns in a mid-season trade.

Those evaluators to whom Olney referred? They’re right. The defensive metrics are inexact. The only certain thing about defensive numbers are that they’re uncertain. But we can gather plenty of bits of information from plenty of sources and piece them together to form a conclusion. We’ve already started with the two quotes. Let’s now go back in history a bit to know what Bruce once was.

Bruce once was a premium defender. At least, that’s what the numbers say. By the way — for the rest of this post, I’m drawing a line in the sand. Bruce had surgery to repair a torn meniscus in his left knee early in the 2014 season. Ever since then, his defensive numbers have been bad. Ever before then, his defensive numbers were good. That doesn’t seem insignificant, so we’re splitting Bruce’s career in two parts: pre- and post-2014. The pre-2014 sample spans nearly 7,000 innings. The post-2014 sample spans nearly 3,000. Two solid samples, even for defensive numbers.

Anyway, that first part of Bruce’s career, from 2008-13, Bruce was regarded highly in the field. I set a minimum of 2,500 innings played in right field over those six years to get a pool of 30 right fielders, combined UZR and DRS figures, and found that Bruce ranked fourth with roughly +5 runs saved per year, right behind Ichiro Suzuki and right ahead of Nate Schierholtz. The arm was seen as a slight plus, he was average at preventing errors, and the range was seen as a definite plus.

I did the same thing for the most recent years, following the knee surgery. For 2014-16, I set a minimum of 1,000 innings played in right field to get a similar pool of 32 right fielders. Same methodology, Bruce now ranks 23rd with roughly -5 runs saved per year, right behind Jose Bautista and Ryan Braun and right ahead of Shin-Soo Choo and Nelson Cruz. The arm is no longer seen as a plus, the errors are still average, and the range is perceived to have taken a huge hit. The metrics see about a 10-run swing per year, and that would cost Bruce roughly a full win of value, annually. This year, Bruce is already at -12, albeit in a limited sample prone to fluctuation.

But we can go deeper than all that. Baseball Info Solutions breaks Defensive Runs Saved down into more granular bits of information. I took all that information, split it into our two chunks of Bruce’s career, prorated each to 1,000-inning scales, and prepared the following table:

Jay Bruce Defensive Runs Saved Breakdown
Year Shallow Medium Deep Range Runs | Adv. Opps Extra Bases Adv. Rate Kills Arm Runs
2008-13 3 3 -1 5 | 92 42 45.6% 5 1
2014-16 2 2 -8 -4 | 96 48 49.5% 4 -2
-All figures presented on per-1,000 inning scale
Shallow/Medium/Deep: Runs saved, based on location
Adv. Rate: Percentage of baserunners taking an extra base on advancement opportunities
Kills: Outs made by throws directly to base, without assist by cutoff man

The difference in the arm is relatively small: a handful more base-runners have ran on Bruce, and he’s done a slightly worse job of throwing them out. That comes out to about three runs a year. The big hit is in the range. The deep ball was never Bruce’s strong suit, but ever since 2014, he’s graded as a disaster when going back on the ball.

Let’s work in some Inside Edge numbers, too. Inside Edge buckets defensive plays by difficulty. To mitigate sample concerns, I like to group all the non-routine plays into one bucket, creating routine plays (90-100% conversion rate) and non-routine plays (less than 90%). The non-routine plays are where the real difference in fielder ability is found. This data doesn’t go back far enough to include the pre-2014 Bruce, but we can say that, since 2014, Bruce has converted the non-routine play 36% of the time, against a league-average of 43%, ranking him 22nd out of 32 — right in line with the DRS and UZR evaluations over the same time span.

Our last piece of information is video. Using our Inside Edge fielding spray charts, I found five plays Bruce missed this season, and five plays of similar difficulty which Bruce made this season, and rendered them into .gif form. They’re presented, without comment, in alternating order below, beginning with a miss:

You’ve got it all. You’ve got the defensive numbers, split into two chunks. The first calling Bruce a +5 fielder, the second calling Bruce a -5 fielder, with knowledge of a knee surgery splitting the two. You’ve got separate bits of information from two reputable reporters, quoting scouts who think Bruce is better than the numbers indicate, knowing he’s currently at -12 on the season. You’ve got the breakdown of Defensive Runs Saved, indicating a decline in Bruce’s ability to go back on a ball representing nearly the entirety of his now-poor range figures. You’ve got Inside Edge agreeing with the metrics, and you’ve got 10 video clips evenly displaying both good and bad examples of Jay Bruce defense.

The opinion of Bruce’s defensive ability is the key in deciding his trade value this summer, and what he’ll bring to whichever club acquires him. With all the information being presented to you, what’s your opinion?

August used to cover the Indians for MLB and, but now he's here and thinks writing these in the third person is weird. So you can reach me on Twitter @AugustFG_ or e-mail at

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7 years ago

2014 also coincides with Billy Hamilton playing in CF next to him. I’d imagine Hamilton’s huge range has affected the amount of fly balls that Bruce attempts to catch

7 years ago

Particularly because he went from having Choo in CF in 2013. Huge range difference had to affect it somehow

7 years ago

If Hamilton is catching balls that Bruce used to get to, it may not penalize Bruce but he doesn’t get the positive value for catching the ball that he used to. Also, it wouldn’t be shocking to hear that Bruce positioned himself differently when playing next to Hamilton than he did when he played next to Choo in 2013.

7 years ago

I was just throwing out ideas. I think it’s more likely that Bruce is now a slightly below average fielder who is just having a bad defensive year. We accept that decent hitters can have bad years, but it seems like people expect defensive metrics to be perfect indicators of true talent level and never fluctuate.

Dane Roberns
7 years ago

I have no evidence that such interaction exists, but it would make sense intuitively if it does exist. He doesn’t get docked for plays that Hamilton takes in his zone, but it does limit his chances at making plus plays. I’d think it possible that Hamilton could diminish Bruce’s apparent positive impact if the portion of his sample he is eating into are mostly the routine and difficult plays Bruce would have made.

7 years ago

“any ball that the good defender gets to that is also sometimes caught by the fielder in question is a plus for that fielder.”

Does this mean that on a play where both Hamilton and Bruce are able to get in position to field the ball, and where Hamilton ultimately makes the catch, Bruce still gets some positive credit? That goes against my understanding of how these situations are treated by UZR.

7 years ago

That seems like a somewhat flawed comparison. I’d have to imagine the percentage of balls in play that the CF and RF can both reach, rather than just one or the other, is much higher than the same split for a 3B and SS. The nature of BIPs hit to OFs lends to their range overlapping more often. I’m sure Bruce defers to Hamilton in any and all cases where they can both get to the ball, and Bruce gets none of the credit in any of these cases, whereas he’s punished to some extent for BIPs that neither he or Hamilton could get to.