There is still plenty of time for another player to be brought in and things to shake up the depth chart, but here is how I would interpret the current left field setup with the signing of Eric Byrnes (scroll down for news post).

Eric Byrnes: He’s mashed lefties throughout his career and hit lefties pretty well even in his down years, and plays plus defense.  That combination makes him a good fit for Seattle, allowing them to pair him with a left handed outfielder in a platoon.  That he’s dirt cheap allows them to ditch him if his hamstring starts bothering him or if he’s showing his age, and GM Jack Zduriencik indicated in his initial announcement that Byrnes would have to earn his roster spot.  Byrnes has indicated that he has no qualms with being part of a platoon.

Ryan Langerhans: Perhaps the top candidate to platoon with Brynes, Langerhans is essentially the outfield version of Jack Hannahan.  He has a great glove (in all three positions), a decent approach at the plate, can hit a few home runs and swings and misses a lot from the left side of the plate.  Langerhans’ bat will keep him out of the lineup at times, leaving the door open for less desirable scenarios that we’ll get to shortly.  Langerhans is on a split contract, meaning he can be sent to the minors without the risk of losing him (as I understand it).

Michael Saunders: I’ve got to think that the Byrnes acquisition helps Saunders’ chances of making the Opening Day ballclub.  Before the signing, Seattle was looking at a playing the matchups rather than a strict platoon which would have given Saunders unpredictable at bats had he made the team.  With a strict platoon, Saunders can get regular playing time against right handed pitchers, and given Byrnes’ and Bradley’s respective injury histories he could get his fair share of at bats against lefties as well.  Obviously, he’d have to significantly out-hit Langerhans in Spring Training after his poor showing in September.

Milton Bradley and Ken Griffey: If Byrnes and Saunders make the team, you’ve got to think that it cuts into the time in the outfield Bradley sees and the number of at bats Griffey receives, both of which should be seen as good things.  If it’s Langerhans and Byrnes, manager Don Wakamatsu would be tempted to run Bradley out in the field instead of Langerhans to get another bat in the lineup (Griffey). Griffey is at his best when he’s well rested, and he’s an asset as a pinch hitter, so the more games he starts on the bench the better.

I can really get behind a Saunders/Byrnes platoon.  Let’s see if they’ll be given that opportunity or if a bigger fish will be brought in.  I can’t see Zduriencik letting this acquisition stop him from improving the club further if a deal falls in his lap.

Edit to add: In the comments Rob brings up the possibility of a Byrnes/Bradley outfield platoon, with Langerhans being a true extra outfielder.  That is a definitely possibility if Wak thinks Bradley can stay healthy in the outfield, and one that would give Griffey the bulk of the DH time against right handers, which wouldn’t necessarily be the worst thing in the world (but far from ideal, in my mind).