Alex Gordon, UZR, and Bad Left Field Defense

Since Alex Gordon moved into first place in position player WAR (although he’s now second again), quite a bit of back-and-forth discussion has occurred on if he is this season’s best position player. Most of the talk revolves around how much stock  should people put into defensive statistics. Our own Dave Cameron has already taken a stab at the subject earlier in the week. Alex Gordon is getting close to two wins of value from his defense, a considerable jump from his previous seasons. After looking at the inputs used for UZR, it is not Alex Gordon’s performance going to new levels, but the lack of talented defenders in left field making him seem better.

Since Alex Gordon has moved to left field, he has put up decent defensive numbers, but not the level of 2014.

Season: UZR, UZR/150
2010: 3, 6 (partial season)
2011: 12, 12
2012: 15, 12
2013: 9, 7
2014: 24, 28

Gordon has already saved more runs than in previous seasons and is on pace to save twice as many by the end of the season… kind of. UZR has two components: what a player does and what the rest of the league does. Let’s start with Gordon’s production and then move to the league-wide values.

Outfield defense has three components, Range (ability to field balls), Arm and Errors. Gordon has a great arm and his LF values since 2011 have ranged from 8 Runs to 11 Runs, so no change there. His Error component has gone from 0 to 2 Runs. Again, not the reason for the jump. The key difference is in his Range value at 14 Runs because his previous high was just 4 Runs. It seems like Alex is getting to more balls in play, but the reality is that he probably isn’t.

UZR uses Baseball Info Solutions numbers, so we can look to see if Alex is actually getting to any more balls in play. They track the number of balls a fielder gets to in his Zone and those out of his Zone. In 2014, Gordon is at a career average for getting to balls in his zone (.916). The value is not too far off his previous values between .913 to .923. The gain is not here. For making plays out of his zone, I have to do a little math. I have the raw number of out-of-zone (OOZ) plays, so I will divide them by the number of innings played each year to get a rough estimate of his OOZ ability.

Year:  OOZ plays, IP in LF, OOZ/IP

2010: 21, 486, 0.043
2011: 74, 1309 , 0.057
2012: 89, 1424, 0.062
2013: 110, 1364, 0.081
2014: 87, 1059, 0.082

He is getting to a few more balls out of his area, but the numbers are close to his 2013 values when he had a -2 UZR Range value. In all, Gordon has done a bit worse with balls in his zone and a bit better with balls out of his zone which makes it all pretty much a wash. Basically, Gordon is getting to just as many balls as he did in previous seasons.

Now moving on to the second component of UZR, the rest of the left fielders. UZR is set so a zero value means the player is league average in defense for his position. Since we know Gordon’s defensive values for his arm and errors aren’t causing the jump, I will concentrate on the range values. Here are the league average values for in and out-of-zone values compared to Gordon’s values and the difference.

In Zone
Year: League%, Gordon%, Difference
2010: 87.1%, 91.7%, 4.6%
2011: 90.4%, 92.3%, 1.9%
2012: 89.7%, 91.3%, 1.6%
2013: 90.6%, 91.8%, 1.2%
2014: 88.4%, 91.6%, 3.2%

Out-of-Zone
Year: League Rate, Gordon Rate, Difference
2010: 0.049, 0.043, -0.006
2011: 0.065, 0.057, -0.008
2012: 0.058, 0.062, 0.004
2013: 0.066, 0.081, 0.015
2014: 0.057, 0.082, 0.025

It may or may not be that the average left fielder’s performance has declined; it could just be an instance of year-to-year variance we’re seeing. In every season, however, Gordon has outperformed the league-average rate.  Gordon is making fewer plays in his zone this  season, but compared to the rest of the league, he is quite a bit better. The same is happening with OOZ plays.

With individual position UZR values, the baseline values can move around quite a bit. There are only 30 inputs into the baseline values, so if just a few players move to a new position or get hurt, the zero value can change. The baseline values for hitting stats like wRC+ can move also, but the swing won’t be as dramatic with over 240 inputs. With offensive stats, position changes don’t matter, so only players not playing changes the inputs. Even if the top four to five hitters are lost for the season, the baseline will stay fairly constant. Now consider if wRC+ is based on just those players at one position. A couple players missing time could really change the baseline, just as it does with UZR.

So what happened from 2013 to 2014. A lot of stuff. Aging. Injuries. Position movement. Here are the top-ten left fielders ranked by there 2013 left field range values. Their 2014 range values and comments on the change are added.

Name: 2013 Range Runs, 2014 Range Runs, Comments
Starling Marte: 13, 3, Missed 16 games for injury and played some CF
Andy Dirks: 10, NA, Missed entire season on the DL (back)
Carl Crawford: 9, 3, Missed 41 games because of injury
Andres Torres: 8, NA, Minors
Alfonso Soriano: 8, -2, Can’t hit and more time in RF
Yoenis Cespedes: 7, 0
David Murphy: 7, -1, Playing RF > 95% of the time
Matt Tuiasosopo: 6, NA, Minors
Chris Heisey: 5, 7, Limited action, with drop in LF talent has a 32 UZR/150 in LF
Eric Young: 5, 5, Limited playing time because of bat
Total: 78, 15

What a contrast from the previous season. Three of the top eight haven’t played in the majors this season. Only one of the ten as seen his numbers go up (Chris Heisey).

As I’ve noted before, this is one possible area of consideration for the UZR. A potential improvement to the system for the future, and one considered in that linked piece, is a baseline defensive value which is constant from year to year in addition to just UZR. Even if it is harder to hit .300 now than just a few years back, we at least have an idea what a .300 AVG means and can reference it. It would be nice to have a second simple stat which doesn’t change based on the year so we can compare how a player in vacuum is performing instead of having to bring all the yearly data for the league and player and compare them. The first 500 words of this article wouldn’t be necessary if the second metric were available. It could show Gordon’s Range Value is at a +4 Historic Runs (hypothetically speaking) compared to +14 2014 Runs. Maybe each player doesn’t need two values, maybe just a comparison value for the entire season could be available.

Putting it all together, the jump in Alex Gordon’s total WAR to a league leading value really has nothing to do with Alex Gordon. He is the same defensive player he has been over the past few season. What has happened is the league wide level in talent has fallen off in left field thereby boosting Gordon’s numbers substantially. If Alex Gordon gets any MVP love, he may want to thank more than his Royal teammates. The real help came from the rest of the league.





Jeff, one of the authors of the fantasy baseball guide,The Process, writes for RotoGraphs, The Hardball Times, Rotowire, Baseball America, and BaseballHQ. He has been nominated for two SABR Analytics Research Award for Contemporary Analysis and won it in 2013 in tandem with Bill Petti. He has won four FSWA Awards including on for his Mining the News series. He's won Tout Wars three times, LABR twice, and got his first NFBC Main Event win in 2021. Follow him on Twitter @jeffwzimmerman.

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Deelron
9 years ago

Mike Morse, LF.

DD
9 years ago
Reply to  Deelron

Dom Brown, LF.

Nivra
9 years ago
Reply to  DD

Matt Kemp, LF

Mack
9 years ago
Reply to  Nivra

Shin-Soo Choo and Michael Choice, LF

Payroll
9 years ago
Reply to  Nivra

Josh Willingham, LF

Carter
9 years ago
Reply to  Deelron

Career paths can be so odd. I remember Mike Morse making his debut for the mariners as a shortstop.