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PRO

It has been called to the CEO's attention that the Mariner defense may be THE most ruinous ever to disgrace a baseball field.  I guess the previous titleholders were the 2005 Yankees, with the prosecution's exhibit A being the players' UZR's.  In terms of player runs below and above average the M's are at a pace to break records held by the entire population of 1900-2019 ballclubs.

Is this true?  It passes the sniff test.  Just going by the names, you've got Jay Bruce (yuk), Edwin Encarnacion (yuk), Ryon Healy (ouch), Domingo Santana (an extreme bat-first player), and a RF playing CF.  Into the bargain, who knows where Narvaez' defense is and I assume that Daniel Vogelbach is one of, if not the, worst 1B's in baseball.  If there were a worst defense in baseball history this is what the names would look like.  Also, DER/BABIP is most affected by speed in the OF and the M's OF is clearly a joke.

So.  I'd figured that the M's were bottom 3 in the league, but it hadn't occurred that "bottom 3" meant "bottom 3, All. Time."

.....

Also, a horrific defense would explain the 7-21 slide.  And Felix Hernandez' 6.52 ERA despite pitching much better than he had the last few years.

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CON

Right now Domingo Santana is -11 plays (not runs) in left field, per John Dewan.  THIS SYSTEM of THEORETICAL defensive measurement has us watching where the ball is hit, and counting up how often we think Santana should have gotten to the ball.  This is the system used to accuse the 2005 Yankees of being the worst butchers ever.  But how about other systems?

First of all, the 2005 Yankees won 95 games.  If they had a defense that shows as the very last entrant in a list of 2,000 defenses then .... defense is very negotiable, I'd say.  That would be a thunderous baseball lesson for me.  ... granted, that team had a 115 offense, but so do the M's.  They also had the Big Unit and some aging big names in the rotation.  But with a 94 ERA+ their breakdown looks eerily similar to this year's M's.

Of course that's not my takeaway.  If a team wins 95 games my assumption is that their defense must have been no worse than bad.  Could be wrong.

...

The Mariners' FIP, their fielding-independent pitching, is 4.89, suggesting that their pitchers are throwing pitches (with K, BB, HR, and sometimes GB rate) that should drive a 4.89 ERA, other things (especially defense and park) being average.  What is their actual ERA?  4.84.  THIS SYSTEM of THEORETICAL measurement suggests that the M's defense is exactly AVERAGE.

No way can these names drive an average defense.  But (1) it would be mighty strange, pardner, if history's worst defense had a FIP = ERA, and (2) it would *suggest* that the theoretical catastrophe was not actually hurting the club on the field.

...

Similarly the M's BABIP, their Defensive Efficiency Rating, is #21 of 30 teams in baseball.  They are converting batted balls into outs at a rate similar to many teams in 2019 MLB.  Interestingly this was also true of the 2005 Yankees, though.

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FIX

All that said, Dr. D is the first to allow that a Bruce-Encarnacion-Santana defense is a huge issue.  Just two changes would fix it.

NOW:  Santana-Haniger-Bruce and Healy-Beckham-Gordon-Encarnacion.  This equates to Bad-Dubious-Catastrophic and Bad-Average-GG-Terrible.  That counts up as x2 Terrible and x3 Bad and x1 Average and x1 Excellent.  Like we sez, it's one thing to have a glove-first player or two, but it's another matter to have 5 of your 7 fair-territory defenders to be way glove-first.

Put Kyle Seager in at 3B, Mallex Smith in at CF and you have Bad-Average-Good with GG-Average-GG-Terrible.  That counts up as x2 Bad and x3 Avg and x2 Gold Glove.  Fairly balanced, and the only offense you've "lost" is Jay Bruce vs. Mallex Smith.

Or not,

Dr. D