OAKLAND -- The A’s have been known for their constant roster turnover for the better part of this decade, but this winter could bring one of the more quiet offseasons in executive vice president Billy Beane’s tenure.

There’s a youthful core establishing itself in Oakland. A plethora of young players under team control should keep the front office from having to do much roster crunching. Still, even if there aren’t as many, the A’s will have some decisions to make. Here are five questions they’re facing as the offseason begins:

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1. How many coaches will the A’s lose?
As is often the case with teams in the middle of successful runs, other clubs in need of new managers will look to poach certain coaches in order to replicate that success. The A’s already lost third-base coach Matt Williams, who accepted a job in Korea to manage the KIA Tigers of the KBO League. Bench coach Ryan Christenson and quality control coach Mark Kotsay have also interviewed for open managerial positions around the league over the past couple of weeks.

“Matt Williams has been a Manager of the Year and deserves another opportunity. Ryan Christenson has been fantastic in our organization and Mark Kotsay also has those qualities,” A’s manager Bob Melvin said. “I think there are a number of guys on our staff that will have opportunities down the road, and that makes me feel good as well.”

No matter how many coaches depart, Oakland feels good about being able to elevate some of its Minor League staff members, many of whom coached these young A’s who have now arrived in the Majors.

2. Will Blake Treinen return to the club?
This time last year, Treinen was coming off a historically dominant campaign as the A’s closer that earned him a record-setting $6.4 million through arbitration. Due to get a bump in salary through arbitration again this offseason, Treinen is a candidate to be non-tendered after a poor 2019 that saw him lose the closer’s role to Liam Hendriks, who turned in an All-Star season. Treinen could come back to Oakland, but it’s hard to see that happening at his projected salary for next year.

3. Was Khris Davis’ 2019 season just an outlier?
You could look at Davis’ 23-homer season with a career-low .679 OPS one of two ways. Either he’s due for a bounce-back season, or he’s regressing. The A’s are banking on this being a one-off, something Davis has earned after three straight 40-homer campaigns, including a league-best 48 in 2018. The slugger will be 32 years old entering 2020, looking to hit his way back into the cleanup spot after finishing '19 near the bottom of the order.

4. What will happen at second base?
Jurickson Profar's production improved as the season went along, but his defensive flaws at second base remained an issue all year. The A’s will have the option to non-tender Profar in the offseason, but even if he does return, it’s likely to be in more of a utility role. Franklin Barreto, Jorge Mateo and Sheldon Neuse all figure to be in the mix for the second-base job entering Spring Training. Oakland could also look for help via trade or free agency.

5. How will the club address its bullpen woes?
Leading the Majors with 30 blown saves, the bullpen was a clear weakness for the A’s. Top prospects Jesus Luzardo and A.J. Puk arrived late in the year to help with some big innings to close out games, but both will slot into the starting rotation in 2020. Aside from Hendriks and Yusmeiro Petit -- whose club option was exercised by the A's -- there aren’t many reliable arms on the current roster.

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