In 2012, much like 2011, the Mariners were an elite, or at least a very good, defensive team. They were 8th in UZR and 9th in DRS, showing above average range and avoiding errors (though their arms were below average). Since the beginning of the 2009 season, the Jack Z era, the Mariners are 5th in UZR and DRS with the 4th best range of all the teams in Major League Baseball. It hadn’t lead to wins, since they have been the worst offensive team since then, even using park factors and are one of the worst pitching teams since then using defensive independent metrics and park factors. The Mariners are the 3rd best team (behind the Rays and Reds) in difference between FIP and ERA. While some of that could be the park, defense also plays a factor as they are the 8th best in difference between ERA and FIP on the road. You can point to the runs, even if the problems in defensive metrics don’t allow us to arrive at the exact number, that their elite defense, especially with a team that has been horrible in nearly every other facet of the game, has saved the Mariners.

With all this said, their seems to be some kind of shift in the Mariners philosophy this off-season. Without going into detail about how the Mariners have been acquiring a lot of bad fielding corner outfielders that should be playing 1st base or DH, let’s look at the Mariners main offensive¬†acquisitions (non-catchers)¬†this off-season along with their 2012 UZRs:

Robert Andino: -3.5

Kendrys Morales: 2.2

Jason Bay: -1.8

Michael Morse: -8.9

Raul Ibanez: 1.8

Mike Jacobs: -2.4 (FRAA since he had limited time in the Majors).

As you can see, it appears that the Mariners are taking a step back defensively, especially when you consider that the two positive UZR players, Ibanez and Morales, are not only considered poor defenders, but have played a significant amount of time at DH. So while the projection systems will be coming soon (I think the Mariners ZIPs comes in later this week), giving us a better idea of what the Mariners defense (and offense for that matter) should look like, I wanted to do a simple projection that I’ve used before. Defensive aging curves are not as readily available or developed as offensive aging curves, but it is generally thought and shown that once beyond ages 22 to 24, players usually begin to get worse defensively (meaning the aging curves are much more aggressive than for hitters). To create a very simple aging curve that I wouldn’t live or die by, but that might be useful enough for this post, I broke down the UZR’s for each age (24 to 40) and will adjust each player’s projection based on age.

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24: 25.6 in 5 players, 5.12 per player

25: 13.9 in 19 players, .73 per player

26: -36.9 in 16 players, -2.31 per player

27: -29.4 in 7 players, -4.2 per player

28: 35.2 in 14 players, 2.51 per player

29: 22.92 in 16 players, 1.43 per player

30: 31.6 in 13 players, 2.43 per player

31: -13.5 in 13 players, -1.04 per player

32: 10.9 in 9 players, 1.2 per player

33: 2 in 4 players, .5 per player

34: 2.8 in 3 players, .93 per player

35: -9.4 in 3 players, -3.13 per player

36: 6.7 in 6 players, 1.12 per player

37: 0

38: 8.7 in 3 players, 2.9 per player

39: 0

40: 0

Because of the survivor bias, we don’t really see a correlation here. So we would adjust for age in this post. What we will do though is look at the 3 major defensive metrics, UZR, DRS, and FRAA for each player over the past 3 years (the general rule is that three seasons is what is considered a significant sample. If a player has less than 3 years of experience, or has not been in the Majors all 3 years, obviously we just throw that year out when it comes to DRS and UZR. If they were in the minors, we will still use FRAA) and create an average for the 9 different figures. We won’t look at catchers (because their are better metrics to use other than the basic defensive metrics when it comes to them, especially when we are looking at things like pitch framing), but we will look at 13 other Mariners that I think have a significant chance of making the team.


Justin Smoak: -3.9

Kendrys Morales: -.8

2B: Dustin Ackley: 3.04

SS: Brendan Ryan: 17.6

ryan is good

Robert Andino: 3.08

3B: Kyle Seager: -.2


Michael Saunders: -.7

Franklin Gutierrez: 3.7

Michael Morse: -7.3

Raul Ibanez: -11.9

Jason Bay: -3.2

Casper Wells: 2.57

Eric Thames: -4.21

According to these projections, it looks like the Mariners defense will be below average in 2013, 2.32 runs below average. This isn’t far below average, so they won’t be an extremely poor defensive team (until you add the catching into it, which currently stands at Jesus Montero and Ronny Paulino, both below average catchers last year), but they won’t be the strong defensive team they were. Whether the defensive sacrifices will help their offense enough to compensate for this projected loss of defense remains to be seen and we will take a deeper look into this in the very near future.