For a team still in the rebuilding/development stages, the annual unknowns of spring training aren’t quite as pressing as they might be for a contender. The A’s focus will be on the regular season and the continuing maturation of key young players, not those tired old spring concerns about fifth starters and fifth outfielders.

Starting Tuesday, when pitchers and catchers report to Hohokam Stadium in Mesa, Ariz., the team will seek to figure out which prospects are ready and formulate a timeline for the rest of the up-and-comers.

1. Is the A’s projected center fielder ready to go?

Oakland acquired Dustin Fowler from the Yankees in the Sonny Gray trade last year, and Fowler, 23, is coming back from a grim knee injury incurred in a collision with an unpadded electrical box in Chicago. Fowler was rated a top-10 prospect in New York’s system, and if fully healthy, he’ll be the A’s primary option in center.

His injury, a ruptured right patellar tendon, was devastating and led Fowler to sue the White Sox and the state agency that runs their ballpark. Last month, he said he was running at about 85 percent and he is scheduled to play in Cactus League games before the end of February.

Should Fowler experience a setback, the team has little depth in center, one reason the A’s made Austin Jackson a one-year offer this winter. Boog Powell, Jake Smolinski and Ramon Laureano (acquired in a minor-league deal with the Astros) are the other options.

2. When will A.J. Puk arrive?

The left-hander, Oakland’s top pick in the 2016 draft, is a potential star, and unlike last year, he’ll get more than a cursory look this spring. Barring disaster, Puk, 22, could be in the A’s rotation this year: He’s 6-foot-7, he struck out 184 batters in 125 innings last year, and he throws in the mid- to upper 90s. Oakland has few sure things when it comes to starters going into 2018 — if Puk gives the team a good reason to be promoted, he’ll get his shot sooner than later.

In the meantime, Puk’s spring appearances will be must-see. And keep an eye on James Kaprielian, also acquired in the Gray deal. He will throw off the mound in March and could pitch in minor-league games in May.

3. Will Bruce Maxwell remain the team’s top catcher?

Maxwell, 27, has been slotted behind the plate when it comes to the A’s young core, especially with Sean Murphy a good two-plus years from the big leagues. The A’s have insisted that Maxwell remains the everyday catcher, but Maxwell has created a little more drama than club officials would like. Though his October arrest for allegedly drawing a gun on a fast-food delivery person is unlikely to put him in jail, his case has yet to be settled and he might receive a suspension from the league. The team was supportive of Maxwell’s right to kneel during the national anthem in September, but there are those in the organization who are concerned that Maxwell’s anthem stance, and its backlash, could be a distraction.

In addition, his numbers weren’t what he or the team had hoped after moving fan favorite Stephen Vogt to make room for Maxwell: Over the course of several stints with the team, Maxwell hit .207 with three homers and 22 RBIs in 76 games. But the A’s have no other left-handed-hitting catcher on the 40-man roster and presumably would have to look outside the organization were they to sour on him.

4. What happens to Renato Núñez?

The corner infielder/outfielder, who is out of options, has a lot of pop but no ideal position when it comes to a big-league roster. Could the 23-year-old, who has played at every level with the team’s young core, make the roster as a bench player? He’s not as proficient defensively as utilityman Chad Pinder, nor is Núñez a speedster, so he’d be essentially a pinch hitter, but he is right-handed, which is a plus for the platoon-loving A’s. The A’s might look to move Núñez before the season, depending on whether ...

5. Is there a roster spot for Brandon Moss?

Moss, a popular member of Oakland’s 2012-14 playoff teams, returned recently in a deal with Kansas City. Because he’s an experienced hitter and the A’s owe him $5 million, there’s an assumption he’ll make the roster. That’s not necessarily the case: Oakland took on that cost to acquire lefty Ryan Buchter, making Buchter still less expensive than a left-handed free agent. The A’s won’t sweat swallowing the cost if Moss doesn’t fit; after all, they paid Billy Butler $10 million last year. Moss told The Chronicle he plans to hit his way onto the roster, but it might be an uphill climb considering the A’s have Matt Joyce in right field, Matt Olson at first and a 23-year-old out of options in Núñez.

Six years ago, Moss was in camp on a minor-league deal; he was called up in May, hit six homers in his first nine games and 76 total over three years with Oakland. If he finds that stroke again, the A’s will find a spot for him somewhere.

Susan Slusser is a San Francisco Chronicle staff writer. Email: sslusser@sfchronicle.com Twitter: @susanslusser