So basically if you use wRC which is a stat that is meant to represent how much a player contributes run wise, an "average" player comes out to I believe it was 77 wRC per 600 PAs. I'm not interested in debating the methodology here but if you just look at a ball park estimate that feels about right if you break down what an average team scores in terms of runs. So what I did from there was found out how much wRC you could expect at 105 and 110 wRC+. Each step up equated to some where between 4 and 5 wRC which is pretty handy.

The up shot of all of this is basically that each run you save defensively basically equates to 1% better in terms of hitter. This is a useful thing to keep in mind IMO. For example, let's talk everyone's favorite hot button case.... 2012 Darwin Barney. He had a 75 wRC+ that year. I remember it being quite the point of contention because bWAR gave him a lofty value(4.6 to be precise). Fangraphs for what it's worth had him at 1.9 fWAR. So this was the exact type of situation i was looking at. If Barney were an average defender what would his bat need to be in order to be roughly equal?

Part of that depends on which metric you want to use. I'm not gonna dive into that debate here but the two we're looking at put his DRS at a whopping 28 and his UZR/150 at12.5. So, if we use my quick rule of thumb here an average defender would basically need to be a 103 wRC+ hitter based on his DRS numbers and an 88 wRC+ based on his UZR/150. Given what we know about Barney.... that feels pretty accurate actually. You're talking about some where between a below average and slightly above league average player depending on how generous you wanna be with his glove.

Just figured I'd share this because it's pretty useful when talking about contrasting style players. For example, if you're debating say Schwarber and Joc like we were prior to the season, Schwarber was like-1 to -2 depending on what metric you used defensively and for his career was a 112 wRC+ bat. Peterson in LF is some where between +5 and +7 and had a career 116 wRC+. So if you adjust them based on their defense Schwarber would go down to like 110 wRC+ and Joc would go up to like 121-123. Obviously Joc has played shitty this year but when viewed through that lens you can see why the cubs would prefer Joc