SEATTLE -- While questions remain regarding their starting rotation, the Mariners appear to have one of their deepest and most-talented bullpens in years lined up for 2018.
General manager Jerry Dipoto's big offseason free-agent signing has been hard-throwing right-hander Juan Nicasio, who inked a two-year, $17 million deal and will join a versatile group anchored by 23-year-old closer Edwin Diaz.
David Phelps is also expected to provide a solid boost after being acquired from the Marlins late last season and the club also added right-handers Nick Rumbelow from the Yankees and Shawn Armstrong from the Indians, which allowed Emilio Pagan to be traded to the A's for first baseman Ryon Healy after a promising rookie campaign.

Even with Pagan's departure, the Mariners return the six relievers who threw the most innings for them last year and now add the veterans Nicasio and Phelps to that mix. The club would like to go with an eight-man bullpen if possible, which would mean carrying an extra reliever and better allowing what Dipoto refers to as a "wolfpack" approach that can help absorb innings and keep the rotation fresher.
MLB.com is taking a look at the projected lineup of all 30 teams ahead of Spring Training. Here's how the Mariners might stack up:
BULLPEN IF SEASON STARTED TODAY
Edwin Diaz, RHP
Juan Nicasio, RHP
Nick Vincent, RHP
David Phelps, RHP
Marc Rzepczynski, LHP
James Pazos, LHP
Dan Altavilla, RHP
Nick Rumbelow, RHP
STRENGTH
Nicasio posted a 2.61 ERA with six saves last year in the National League and will split the setup duties with Vincent and Phelps. Along with hard-throwing closer Diaz, that gives Seattle four strong late-inning options and should take pressure off Vincent, who was outstanding until being overworked the past two seasons.

The Mariners are very optimistic about Pazos, Altavilla and Rumbelow, a trio of young power arms, and they have further depth after adding the hard-throwing Armstrong via trade at the Winter Meetings and also having Tony Zych coming back from shoulder issues.
QUESTION MARKS
Phelps needs to show he's fully recovered from the elbow issues that limited him to 10 appearances after being acquired in late July. Rzepczynski and Vincent struggled in September last year, so lighter workloads likely are needed for those two veterans. And while Nicasio is a powerful 6-foot-4, 250-pounder, he also might benefit from less usage after making an NL-high 76 appearances last year.
Rumbelow is an intriguing 26-year-old coming off a very impressive year in the Minors for the Yankees, but hasn't pitched in the Majors since 2015 after having Tommy John surgery in '16.

WHAT MIGHT CHANGE
This group appears pretty well set, with the normal qualifier that Dipoto always figures to be open to adding a veteran non-roster invitee or two on Minor League deals for further depth. The final two spots are certainly up for grabs, however, since Altavilla and Rumbelow have Minor League options and could open the season in Triple-A Tacoma.
Armstrong and veteran right-hander Mike Morin, a recent waiver pickup, are out of options and thus will need to either be kept on the 25-man roster or exposed to waivers. It's also possible that lefty Marco Gonzales could land in the bullpen as a long man if he doesn't earn a starting role, since he's also out of Minor League options. Zych could certainly push his way into the conversation if he can stay healthy after posting a 2.66 ERA in 45 appearances last season, though he does have options remaining.