Breaking down the Mariners: Will the bullpen be the difference?

Feb 14, 2018, 12:32 PM | Updated: 4:10 pm

Mariners closer Edwin Diaz had stretches of dominance and inconsistency in 2017. (AP)...

Mariners closer Edwin Diaz had stretches of dominance and inconsistency in 2017. (AP)


With pitchers and catchers reporting this week and the full squad beginning spring training next week for the Seattle Mariners, we’re taking a closer look at the team in a three-part series. This final piece breaks down the bullpen.

The Mariners saw first-hand last season how important relief pitching can be in the modern MLB, as their starting pitchers dealt with an onslaught of injuries and put more work on the bullpen than they were prepared for.

Seattle wasn’t about to let its bullpen be caught unprepared this season.

Breaking down the Mariners: Lineup | Rotation

General manager Jerry Dipoto focused on adding not just depth but also a key set-up man to improve the bridge to closer Edwin Diaz. The Mariners know they’re not bringing the American League’s most stacked starting rotation into 2018, but they have a shot at having some of the best relief pitching in the league – or at the very least, a bullpen that can take on more innings to keep the pressure off the rotation.

Here’s an in-depth look at the construction of Seattle’s bullpen.


Edwin Diaz, who will turn 24 next month, has the stuff it takes to be a dominant major league closer. He spent the entire month of July 2017 showing that, piling up eight saves in nine chances and maintaining a 1.98 ERA on his way to winning the AL’s Reliever of the Month award. The Mariners could stand to see more consistency out of the right-handed flamethrower, though, as he is still prone to bouts of wildness and unraveling on the mound, so much so that he had to take a break from closing after a rough patch at one point in the first half of season. Diaz is still very much learning the ins and outs of being a relief pitcher, but after seeing how he bounced back in July and again in September after a up-and-down August, the Mariners at least can be confident that he can get back on track after things go sideways. A few less periods of shakiness for Diaz would be quite welcome for the Mariners, but at the very least they have more reliable arms in the pen that could serve as closer insurance than a year ago.

Set-up men

As big as the Mariners’ trade for Dee Gordon was, the offseason addition that could end up having the biggest impact just may end being right-handed reliever Juan Nicasio. That’s because he showed last year that he can handle a hefty workload and be effective while doing so, appearing in 76 games (for three teams) and maintaining a 2.61 ERA and 1.08 WHIP. Nicasio’s signing will take some work off of the plate of Nick Vincent, who had a 3.20 ERA over 69 appearances and finished second in the majors in holds with 29. That pair alone would make for a pretty good 1-2 punch leading up to Diaz, but Seattle also has 31-year-old David Phelps, a midseason trade acquisition who was hampered by injuries for much of his time after coming over from Miami but could be a really important weapon in 2018.

Lefty specialist

Marc Rzepczyski, 32, is back for his second year in Seattle, and while he didn’t have the greatest debut season in a Mariners uniform – he posted a 4.02 ERA and walked just five less (20) than he struck out (25) – a bounce-back year is probably just as likely as a repeat of 2017. Not only that, I would have to imagine manager Scott Servais will have a better handle on how to use Rzepczyski this season after mentioning in 2017 that he thought long periods without game action led to a lack of consistency for the veteran southpaw.

The depth

The Mariners have a nice, long list of relievers with MLB experience that can fill out the bullpen. For the familiar names, there is lefty James Pazos and righties Dan Altavilla and Tony Zych (working his way back from inflammation). All three of those pitchers are 27 or younger and will benefit from having less pressure on them this year due to the additions of Nicasio and Phelps. For the new names, the Mariners have Shawn Armstrong, Chasen Bradford, Nick Rumbelow and lefty Sam Moll, all who have a little MLB experience. And then there’s Mike Morin, who has appeared in at least 47 MLB games three times in his career. It’s a much better crop of arms than a year ago, something that could end up making a world of difference for a team that on paper has a strong lineup and less-than-stellar rotation.

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