Analysis: Evaluating Mariners' Roster With Six Days to Go Until Deadline

The Mariners bullpen is currently the seventh-ranked bullpen by ERA (3.47). But since June 21, the unit has paced the league with a 1.58 ERA and 1.7 fWAR. It also has the second-best K-BB rate (20.3 percent) in that time. 

Seattle plays in a pitcher-friendly park and none of its relievers have significant home run to fly ball issues, so not much regression is to be expected. The highest ERA in the Mariners bullpen belongs to Diego Castillo, who is at a 3.93 while only giving up three earned runs in his past 23.2 innings pitch. 

While this bullpen could potentially use another arm, it is already one of the best groups in baseball now and moving forward. Any "boost" to this group may just yield lateral results, but given how cheap relievers are, I could see Seattle looking to make some sort of addition. Bullpen is just the strength of the team and not the biggest need.

Ty France and Eugenio Suárez are giving the Mariners significant value playing first and third base. Carlos Santana has also been valuable in the first base/designated hitter rotation. 

While there is not much depth behind Suárez at third, this position group has probably been addressed to the fullest extent, barring some injury. However, given Abraham Toro's well-documented struggles, it's possible the Mariners could acquire a versatile infielder who could cover every position on the diamond.

In my opinion, Seattle still needs another starting pitcher or two for its playoff push. Still, Robbie Ray, Logan Gilbert, George Kirby, Marco Gonzales and Chris Flexen have all held down the fort. 

This year, the Mariners own the sixth-best rotation ERA (3.65) in baseball. As such, there is plenty of reason to be optimistic about several members of the rotation going forward, though Gonzales and Flexen have concerning peripherals and predictive stats. 

Gonzales has a 3.74 ERA, but he ranks almost dead-last in strikeout rate amongst qualified starters at 12 percent. He's struggled to manage contact and is now two years removed from his elite walk rate. Flexen, meanwhile, has been solid in his past few starts, going 11 straight outings now without giving up more than three runs. That said, his peripherals and predictive stats are only a little bit better than Gonzales'. 

I could see Seattle looking to upgrade both spots in the rotation and potentially add more if they have concerns about late-season workload management with Kirby and Gilbert.

Cal Raleigh's emergence has been well-documented on this website, and Seattle has to be happy with the value he is giving the club behind the plate. While he strikes out a lot, Raleigh hits the ball hard, takes his walks and is a pretty good defender behind the dish. His 2.0 fWAR puts him ninth amongst all MLB catchers. 

Raleigh looks like he should be a long-term fixture as Seattle's backstop, but the team should definitely look to upgrade its No. 2 option from Luis Torrens, who has not looked good at the plate this year and not much better behind. Torrens has a -0.5 fWAR this year to go with his 52 wRC+. 

J.P. Crawford has been solid at shortstop, but it really has been a tale of two seasons for him. He's been worth 1.7 fWAR while playing average defense at shortstop by defensive runs saved, which is the best (but not perfect) fielding stat for infielders. Crawford has hit just one home run since May 2 and has cooled off dramatically from his hot start to the season. 

Since then, Crawford has put up a 77 wRC+ while slashing .229/.298/.298 and has been worth .1 fWAR. He has been struggling for a while, but Jerry Dipoto has continually insisted that Crawford is the team's long-term shortstop. I do not think the Mariners will make a move, though Crawford needs to figure things out fast. 

Things have not been much better at second base, with the position group slashing .213/.274/.317 on the season with marginal positive defensive value. They have a 72 wRC+ on the year. Toro and Adam Frazier need to be upgraded over, with the former needing time in Tacoma to fix some things. Frazier has performed better as of late, but the Mariners would likely prefer to push him down the roster and utilize him as above-average depth. 

Sam Haggerty has been a pleasant surprise, but I do not buy in his ability to keep this up long-term given his poor walk rate, high strikeout rates, poor chase rates, poor barrel rates and significant BABIP luck. I could see the Mariners acquiring a low-cost infielder who can play up-the-middle.

Outside of Julio Rodríguez, Seattle's outfield has been a revolving door of Jesse Winker, Dylan Moore, Mitch Haniger, Kyle Lewis, Haggerty, Justin Upton, Marcus Wilson, Frazier, Jarred Kelenic, Taylor Trammell, Steven Souza and Stuart Fairchild. 

They have faced key injuries and disappointing lack of production. Winker has been a league-average bat (104 wRC+) with bad defense. Moore has been solid at times but should play everyday. Upton, Fairchild, Kelenic, Souza and Wilson are not on the 26-man roster anymore. Lewis has just returned after an extensive stint on the injured list with a concussion, while Haniger has recently begun a rehab assignment as he continues to work his way back from a high ankle sprain. Like Lewis, however, there is no telling how much defensive value Haniger will provide.

I would be a little surprised if Seattle does not address this position in some way at the deadline, but Dipoto has said he views Haniger and Lewis' return as reinforcements, and there is potential for Kelenic and Trammell to return near the end of the year. That being said, Seattle could use some short-term stability. Its outfield has a 102 wRC+, despite Rodríguez's high mark of 135.