While this has been a fun season filled with winning, not every player has been able to carry their assigned load thus far. One of the main culprits is the man formerly known as Death To Flying Things, Mr. Franklin Gutierrez. Guti is asked to do very little for this team. He used to have to patrol the vast expanse of center field, but now he plays the corner or DH, and typically only starts against left-handed pitching.
In a certain sense, Guti has actually done his job thus far. In 46 plate appearances against southpaws, Guti has a 117 wRC+; it's not the 168 line he put up last year, but it's certainly worthy of a platoon bat. Guti's problem this year: he's been a complete and utter black hole against right-handed pitching. He only has 12 plate appearances against righties, but he's struck out in seven of them. Strikeouts have been an overarching issue this year -- Guti's swinging more while making less contact, even at pitches in the zone, which is a horrible sign.
Unfortunately, there isn't much in the way of worthy replacements waiting in the wings. As it goes with most positions on the roster, the team doesn't have the luxury of depth. The Mariners have a minor advantage in that Nelson Cruz can play in the outfield if needed against lefties, but if Guti is no longer on the roster, another outfielder should be on the 25-man anyway.
Stefen Romero is nominally an outfielder, and he continues to tear up the minors, like he always has. Romero has his fans, but neither of his short stints in the big leagues have gone particularly well, and he certainly shouldn't play center in a pinch. Boog Powell can play center and is generally awesome, but he's a left-handed hitter and really should be playing every day to help further his development, so he's not a great fit for this role.
Shawn O'Malley's already on the big league roster and the team seems to believe he can play some centerfield, but he's best in a utility role, not as someone who has to play, even on the smaller side of a platoon. The only other outfielder on the 40-man roster is Guillermo Heredia. While he throws left-handed, he bats with with right and is considered to be at least a solid defender in all three outfield spots. His results in Double-A have been generally underwhelming, and though already 25 years old, he could probably use some more time in the high minors to get his bat into a serviceable form.
That leaves options outside of the current roster. While teams like the Brewers, Twins, Reds, and Braves are pretty clearly out of it this year, there's not an obvious trade fit on their rosters. Alex Rios is still floating out on the free agent market, but he may be seeking real money and isn't anything better than a lottery ticket. The Rays and the Mariners are willing trade partners; perhaps Desmond Jennings could use a change of scenery, but Tampa may not be willing to give up on him just yet.
One under-the-radar name to keep an eye on: Collin Cowgill, currently in the minors with the Indians. Cowgill was scouted and developed by Dipoto in Arizona, and Jerry acquired him with the Angels back in 2013. Nothing about Cowgill's profile is sexy, and he looked bad last year and again this year, but he's been an above-average hitter against lefties when lumping together the last three seasons, and is worth having around in the organization if available.
Guti deserves a little more time, of course. Part-time players can have trouble getting in a groove, and we're talking about less than 60 plate appearances. Good looks can only get you so far, though. At a certain point, you have to produce, and the Mariners can't hold off exploring their options for much longer if they want to seriously compete. The obvious options aren't pretty, but Guti's game hasn't been, either.