OAKLAND -- The uncertainty surrounding the A’s upcoming season would be enough to cause concern for any manager.

Not only do the A’s have 10 key free agents they may have to replace -- including shortstop Marcus Semien and All-Star closer Liam Hendriks -- they also face potential changes in the front office, with executive vice president of baseball operations Billy Beane reportedly leaving Oakland for a new business venture.

Yet when looking ahead to the 2021 season, A’s manager Bob Melvin remains positive about the club's outlook. Its core remains mostly intact, with talented young arms like Jesús Luzardo, Frankie Montas and Chris Bassitt leading the way on the pitching side and stars like Matt Chapman, Matt Olson and Ramón Laureano reaching their prime.

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“The good news is, we still have a core group of guys we feel great about,” Melvin said. “Some of our younger pitching is probably going to have to step up. We’ll still see how the market plays out. It’ll be a while before we see that. There may be some interesting pickups later on.

“It’s not ideal. We’ve had great contributions by our free agents. But again, we have a group of guys here that we feel really good about.”

Melvin addressed some of the big questions the A’s face this offseason on Thursday as part of the virtual managerial availabilities held by clubs this week in lieu of the Winter Meetings:

What happens with the bullpen?

Where things stand: Along with Hendriks, Yusmeiro Petit, Joakim Soria and T.J. McFarland are also on the free-agent market, meaning Oakland’s bullpen could undergo an overhaul.

Melvin named left-hander Jake Diekman as the obvious candidate to fill the closer’s role, though with the evolution of bullpen usage in recent years, Melvin acknowledged he may have to go to the lefty earlier in games if higher-leverage situations surface. Diekman was lights-out for the A’s in 2020, earning a nomination for the All-MLB Team after allowing just one earned run with 31 strikeouts over 21 1/3 innings. Another candidate that Melvin mentioned was hard-throwing right-hander Lou Trivino.

What Melvin said: “Our bullpen numbers speak for themselves last year. They were really good. We still have some guys -- Diekman, Lou Trivino, J.B. Wendelken -- guys that we really like. And like any year, you expect guys within the system to step up. We’re probably a little bit deeper in starting pitching in our system with our prospects than we are with relievers, but there comes a time when some of those starters might have to do things differently. That’s an area of concern, yet [A’s GM] David [Forst] and Billy [Beane] have always been really good about picking up relievers. Almost every year, we seem to pick up a couple of relievers that give us great contributions.”

What role awaits A.J. Puk in 2021?

Where things stand: Puk, Oakland’s No. 1 prospect per MLB Pipeline, continues his rehab from left shoulder surgery in September. Long expected to anchor the A’s rotation, Puk’s recent shoulder issues have created speculation to whether he might be better suited for the bullpen, a role he performed well in as a September callup in 2019. With four of Oakland's five rotation spots already filled by Luzardo, Montas, Bassitt and Sean Manaea, and pitching prospects like Daulton Jefferies and James Kaprielian reaching the Majors last season, the A’s certainly have enough options to facilitate a potential conversion for Puk to reliever.

What Melvin said: “Where we use A.J., we’ll see. I think right now, the thought is to build him up as a starter, but he could be a bullpen piece for us as well if we feel we’re a little short in the bullpen. The starting rotation is probably an area we’re not as concerned about. They got a lot of experience last year, especially our younger guys.”

How is Chapman's recovery progressing?

Where things stand: Despite winning the American League West, the A's certainly felt the loss of their star third baseman, who underwent season-ending hip surgery in mid-September. Despite the long-term ramifications of hip injuries, the A’s have remained confident that Chapman will return to form, particularly after breaking out in 2019 with a career-high 36 homers while also earning his second consecutive Gold and Platinum Glove Awards.

What Melvin said: “He checked in with me before I could check in with him right after his last update. As far as the hip goes, he’s full speed ahead. He’ll be ready to go. Depending on when everything starts and what we’re looking at for a full season, I don’t think there’s any doubt he’ll be ready to go, and he’s let me know that. We always take a look at our guys, physically, once they get into camp and have some ideas on potential workloads for Spring Training. I expect him to be a full go.”

What would Beane’s possible departure mean for Oakland?

Where things stand: Despite reports that surfaced in October of Beane leaving the A’s for a new sports venture with Red Sox owner John Henry, the “Moneyball” influencer remains a part of the organization. It’s unclear where things stand on that front, but given Beane’s longevity with the club and other front office execs like Forst and assistant GM Billy Owens constantly having their names surface in GM searches around the league, change within the A’s front office in the near future almost seems inevitable.

What Melvin said: “I think one of the reasons our organization has been successful is the continuity. With as much turnover as we have, player-wise, it’s the continuity with the guys in charge that has ruled the day here. On the other hand, I’d love to see Billy Owens get a GM job. It would affect us, but you always want to see guys move up. In Billy Beane’s case, at some point in time, he’s going to do something bigger and better. He’s pretty well-versed in other sports and in the business world as well. If that happens, that’s why there’s a David Forst there to continue what we’ve done for years here. At the beginning of the offseason, it looked like there might be several guys in that group that you talked about not being here. At this point in time, it looks like everybody’s going to be back. I would certainly be fine with that, but you also want to see guys move up and get jobs they probably deserve. It’s tough to keep this many good people all together for a long period of time, and this organization has been able to do it.”