SCOTTSDALE, Ariz. -- The back end of the Giants' starting rotation will move to the forefront among Spring Training priorities.
Chris Stratton and Ty Blach enter big league camp as the favorites to claim the vacancies for the fourth and fifth starter spots. Matt Moore's departure to Texas in a December trade and Player Page for Matt Cain's retirement created the openings.
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However, Stratton and Blach are vulnerable to being unseated by Tyler Beede, Andrew Suarez or Derek Holland as pitchers and catchers reported to big league camp on Tuesday.
"We're not locked in yet. There's nothing set in stone," manager Bruce Bochy said. "But when I look at Blach, what he did last year when [Madison] Bumgarner went down, I think he showed that he's a Major League pitcher."
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As for Stratton, Bochy said, "The noise he made when he came up takes a little bit of that unknown factor away for him and for us."
This jousting for position behind the Giants' top three starters, Bumgarner, Johnny Cueto and Jeff Samardzija, represented the Giants' most wide-open competition, which will begin with Wednesday's initial workout for pitchers and catchers.
Here's a quick look at the pros and cons for each rotation candidate, in alphabetical order:
Beede
Pros: At 24, he appears poised to fulfill the potential that made him the Giants' first-round Draft choice in 2014. Beede might have ascended to the Majors last year had he not sustained a groin injury.
Cons:Ranked second among Giants prospects by MLB Pipeline, Beede certainly passes the eyeball test. That is, he looks like a big leaguer. But his 19-25 professional record suggests that he needs to gain more polish.

Blach
Pros: Blach filled this role adequately last year as a rookie, finishing 8-12 with a 4.78 ERA in 34 appearances (24 starts). That experience should make Blach even better this year.
Cons: Skeptics believe that Blach is just another soft-tossing lefty. They cite his 73 strikeouts in 163 2/3 innings in 2017.

Holland
Pros: Experience. The 31-year-old left-hander broke into the Majors in 2009 and has compiled a 69-64 record with a 4.57 ERA. Holland has logged 184 starts in 208 big league appearances.
Cons: Holland's not the same pitcher who finished 16-5 with four shutouts in 2011, his best year. Last season, he went 7-14 with a 6.20 ERA in 29 games (26 starts) for the White Sox.

Stratton
Pros: During a three-start stretch last August, Stratton didn't look like a big leaguer. He looked like an All-Star. He blanked Washington and Milwaukee over 12 2/3 innings in consecutive starts and recorded a pair of 10-strikeout efforts.
Cons: Lacking above-average velocity, Stratton has to stay one step ahead of hitters. He must continue to learn to make the most of what he has to survive in the Major Leagues.

Suarez
Pros: Rated the organization's ninth-best prospect by MLB Pipeline, Suarez began drawing rave reviews from Bochy last spring. The Giants believe that his ability to mix four pitches will take him a long way.
Cons: Suarez isn't overpowering, so he must rely on command and movement to subdue hitters. That approach doesn't always work.