SAN DIEGO -- On the first day of the annual Winter Meetings, the D-backs officially announced the signing of free-agent reliever Junior Guerra to a one-year contract with a club option for 2021.

Relief pitching, along with outfield help, is still among the items GM Mike Hazen and his staff are looking to add.

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Guerra, 35, had a 3.55 ERA in 83 2/3 innings out of the bullpen for the Brewers in 2019. The right-hander was eligible for salary arbitration and was non-tendered by Milwaukee. The deal with the D-backs calls for him to receive $2.55 million in 2020 with a club option for 2021.

“We’ve liked him for a while,” Hazen said. “We think he can pitch in a variety of roles in the bullpen, move from the middle to the back of the pen. He can pitch against righties and lefties and gives us a lot of flexibility and options for [manager Torey Lovullo] to use during games. We feel like we have to add a couple pieces to the ‘pen, and this was going to be the first one.”

With Archie Bradley penciled in as the closer, Guerra joins setup options like lefty Andrew Chafin and righties Yoan López, Matt Andriese and Kevin Ginkel.

Still, Hazen will continue to try and add even more depth.

“I don’t think we have to [add another reliever], but that’s probably our goal,” he said.

The D-backs are also in need of outfielders. They’d like to add a center fielder, which would allow them to play Ketel Marte primarily at second base. They also need a right fielder to replace the free-agency departure of Adam Jones and the loss of Steven Souza Jr., who was non-tendered.

“It’s hard to say what we could end up dealing with,” Hazen said. “I think both free agent and trade, there’s options out there for us to explore.”

One option is Japanese free-agent center fielder Shogo Akiyama, but Hazen said the team had not yet sat down with him.

Would they like to meet with him?

“We have not met with their agents yet, so I don’t have a plan on that just yet,” Hazen said. “I’ve said this before, we’re exploring all areas of the outfield market.”

The D-backs won 85 games last season and have about $30 million in payroll flexibility to use this offseason. Still, to have a team that can contend with the Dodgers in the National League West, the D-backs will have to not just look at free agents but also the trade market.

That could mean having to part with Robbie Ray, who is one year away from free agency, or some of the depth the team has built over the past two seasons in the farm system.

“I feel like our team has been competitive,” Hazen said. “I feel like we have the ability, with the right acquisitions, to continue to be competitive and trying to move the ball forward from where we were last year. We have a lot of work to do to get there. We are willing and open to doing that, adding that talent, any way we can. We’re going to have to be open-minded to trading players. And we are.”

The decision to non-tender starter Taijuan Walker, however, means that if the D-backs were to deal Ray, they would likely need to find a way to get pitching back.

“We’ll probably be very mindful if we traded from our starting pitching depth,” Hazen said. “I’ll put it that way. At this point, if we made a trade, I would imagine we would be adding back in some way, somehow, underneath that. I still think we have a decent amount of depth, but we would start to get a little thinner if we choose to [trade a starter]. We’ll still be opportunistic there, but I would imagine if we made a trade at this point, we’d be addressing the starting pitching some other way.”

As of Monday, though, nothing was imminent.

“A lot of phone calls, a lot of internal discussions, but nothing too crazy yet, no,” Hazen said.