The American League West is third in our series of 2018 Early Bullpen Outlooks and will wrap up the AL side of things.

The AL West has some solid bullpens with some dependable closers at the helm, but none who really inspire confidence as early or even mid-round fantasy selections. At least not yet. The Angels have some guys with potential, Mariners' closer Edwin Diaz flashed a bit last season, and Astros closer Ken Giles has tantalizing "stuff" that he just needs to put together.

Let's take a look at the American League West and see who can help fantasy teams this coming baseball season.

Houston Astros

Closer: Ken Giles

Volatility Rating: Solid

Other Relevant RPs: Chris Devenski, Will Harris, Hector Rondon

The Houston Astros really, really want Ken Giles to be their elite closer for many years to come. They gave up a ton to get him from the Philadelphia Phillies and gave him plenty of chances in the ninth inning to prove that he could do it. He showed his tantalizing upside in the regular season, posting 34 saves with a 2.30 ERA and 11.92 K/9, but then struggled in the postseason to the extent that he was even pulled from the role. That might make the ground under him a little less solid than it would have been, but Giles is still the team's closer and will have every chance to keep his role. If he struggles, however, the Astros have several excellent arms that could take his place.

Chris Devenski has had two excellent seasons out of the Houston bullpen. Last season, he posted a 2.68 ERA with 11.16 K/9 in 80.2 innings of relief. He saved four games, and is the logical choice to replace Giles in the ninth inning if he struggles or gets hurt. Devenski would be an immediate must-add if ever named closer, but even as a setup man, he can provide strong enough ratios to be worth owning in deeper leagues. He's a must-own in any holds leagues.

Fantasy Must Own: Ken Giles (all formats, unless his confidence is shot and he implodes in Spring Training), Chris Devenski (all holds formats, some deeper mixed and AL-only leagues)

Los Angeles Angels

Closer: Blake Parker

Volatility Rating: Questionable

Other Relevant RPs: Cam Bedrosian, Jim Johnson

The Los Angeles Angels had an up-and-down year with their bullpen in 2017. They were excited about Cam Bedrosian, but he struggled and ended up injured. But then Blake Parker came mostly out of nowhere and looked great, showing that he might be the closer the team has been looking for ever since Huston Street stopped being effective. Parker saved eight games last season, putting up a strong 2.54 ERA with 11.50 K/9 in 67.1 relief innings. He gradually worked his way up the bullpen pecking order and enters Spring Training as the favorite to work the ninth inning in 2018.

The only thing keeping Parker from being an absolute must-own in all formats is Angels manager Mike Scioscia's affinity for using the dreaded bullpen by committee. Cam Bedrosian was an elite setup man in 2016, posting a tiny 1.12 ERA and 11.38 K/9 in 40.1 innings. 2017 didn't go nearly as well, as Bedrosian put up a 4.43 ERA in an injury-shortened season. Still, he's shown that he can succeed at this level, and deserves a chance at meaningful innings. Parker will likely start the season as the team's closer, but Bedrosian could be nipping at his heels fairly quickly if he returns to his 2016 form.

Fantasy Must Own: Blake Parker (all formats, assuming he's named closer), Cam Bedrosian (all holds leagues and deeper leagues/AL-only)

Oakland Athletics

Closer: Blake Treinen

Volatility Rating: Solid

Other Relevant RPs: Liam Hendriks, Ryan Dull

The Oakland Athletics have a solid bullpen. No one will jump out at you with elite numbers, but no one will make you cringe either. The bullpen is populated by guys similar to closer Blake Treinen. The A's bullpen is fine, just fine. And there's no sarcasm there. Treinen split 2017 between the Nationals and the A's, saving 16 games and posting a 3.93 ERA with 8.80 K/9. He was markedly better in his time in Oakland though, recording 13 of his saves and posting a much better 2.13 ERA and 9.95 K/9. He enters the season as the team's closer and should have a pretty solid grasp on the role.

Oakland's setup men are similarly good-but-uninspiring. Ryan Dull had an injury-shortened 2017, pitching only 42 innings. He struggled to a 5.14 ERA, but did have a 9.64 K/9. 2016 was a much better season for Dull, when he had a solid 2.42 ERA despite a slightly lower K/9 of 8.84. He'd be in the mix for saves if something were to happen to Treinen, but he doesn't need to be owned in any formats at this point. Same goes for Liam Hendriks, whose 10.97 K/9 is nice, but his 4.22 ERA drops him back to a solid but not great bullpen arm.

Fantasy Must Own: Blake Treinen (all formats, later in drafts)

Seattle Mariners

Closer: Edwin Diaz

Volatility Rating: Solid

Other Relevant RPs: Juan Nicasio, David Phelps

The Seattle Mariners have one of the more exciting young closers in the game today in Edwin Diaz. He's still a work in progress in some extents, but he's already a solid closer with elite upside. Last season, he saved 34 games, posting a 3.27 ERA and 12.14 K/9. All excellent numbers, but his 4.36 BB/9 was concerning and led to some big innings at times. He lost his job for a few games in 2017, but came back strong and will be the unquestioned closer heading into Spring Training.

Setting him up will be new acquisition Juan Nicasio. Nicasio spent 2017 with three different teams, totaling a 2.61 ERA and 8.96 K/9. He's a solid setup man who will bridge the game to Diaz more often than not. He's not a guy with the elite upside of Diaz, but he's worth a roster spot in holds leagues. Same goes for David Phelps. His 10.02 K/9 in 2017 was nice, but a 4.20 BB/9 led to a 3.40 ERA. He could also be worth a spot in holds leagues, but neither Phelps nor Nicasio is worth owning in standard leagues at this point.

Fantasy Must Own: Edwin Diaz (all formats- could be one of the better fantasy closers if he continues to develop), Juan Nicasio/David Phelps (holds leagues only)

Texas Rangers

Closer: Committee (Jose Leclerc, Alex Claudio, Keone Kela)

Volatility Rating:Extremely Volatile

Other Relevant RPs: Mike Minor? Matt Bush?

The Texas Rangers have no clear closer for 2018 and really no clear best candidate. The Rangers bullpen is looking like it might be an issue this coming season, so it wouldn't be all that surprising to see Texas go into 2018 with a closer that isn't currently on the roster. For now, we'll assume that they don't sign a free agent nor acquire one in a trade, so we'll look at what they have available in-house.

Jose Leclerc was part of the ninth inning committee at the end of 2017. He saved two games and posted a 3.94 ERA along with 11.82 K/9. That all sounds pretty good, right? Why isn't he the one in the lead for the 2018 closer role? In 45.2 innings pitched, he put up an absurd 7.88 BB/9. If he happened to learn control in the offseason, he could make noise as a strong closer, but if not, every inning is a big-inning risk with that many walks. Alex Claudio did a workmanlike job last season, saving 11 games while posting a 2.50 ERA. He's a soft tossing lefty who only strikes out 6.10 per nine innings though, definitely not the "closer profile" you look for, especially in fantasy. Mike Minor and Matt Bush both had solid seasons out of the bullpen last year, but they are both expected to compete for a spot in the starting rotation this year.

Keone Kela is an interesting arm and might have a sneaky inside track at the ninth inning in 2018. He's seemingly been the Rangers "closer of the future" for a few years now, but injuries have derailed any chance of that happening yet. He did post two saves last season and a solid 2.79 ERA with 11.87 K/9 in 38.2 innings pitched. He underwent stem-cell therapy in his troublesome shoulder this offseason and is reportedly pitching without pain for the first time in a long time. He'd make a solid closer if he could stay on the field, but that's a huge "if" and makes him a big risk in fantasy drafts.

Fantasy Must Own: No one at this point, but if any of the pitchers mentioned are officially named the team's closer, he would be worth owning, especially if it's Kela.

More 2018 Player Outlooks