PEORIA, Ariz. -- Here are three major question marks for a Padres bullpen that, on paper, looks like a deep group of arms with a few noteworthy flaws:

1. Who's the closer?
Mark Melancon filled the role superbly last season, but he has departed for Arizona, leaving the Padres with a vacancy at the back end. They have a number of options to fill that vacancy -- headlined by Emilio Pagán and Robert Suarez. But there's no clear-cut answer.

Drew Pomeranz was the obvious fit, as the Padres' most dominant reliever over the past two seasons. But he hasn't begun throwing off a mound yet as he recovers from flexor-tendon surgery last August. Pomeranz believes the surgery has addressed a longstanding elbow issue, meaning he'll be fully available when he returns. But that return isn't likely to come until May.

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In the interim, the Padres need someone for the ninth inning. Pagán has pitched three scoreless innings this spring and has made good use of a split-finger fastball, which he's added to his repertoire. But take those spring numbers with a grain of salt, as Pagán struggled mightily down the stretch last season.

Suarez, meanwhile, hasn't quite hit the ground running after a ridiculously dominant 2021 campaign in Japan. He has pitched only three times -- twice in the Cactus League and once in a Minors game.

Other final-inning options include Pierce Johnson, Craig Stammen and, down the road, perhaps Dinelson Lamet if he can acclimate to a short-burst relief role.

Padres manager Bob Melvin says he’s typically staunchly against a "by committee" approach, but he might have to operate that way early in the season.

"I do like knowing," Melvin said. "I like to work back every day, know who's pitching the ninth, at least in my mind. Then you go to the eighth, seventh ... but I'm not sure that's going to be the case."

2. Are there enough lefties?
The Padres' bullpen seriously skews right-handed this season, with Tim Hill as the only left-hander who has a guaranteed place in the 'pen while Pomeranz heals. That could create some matchup problems, though perhaps not as many as you'd think, with the right-handed Stammen having operated with reverse splits over the past two seasons.

In a way, Stammen says, breaking a bullpen into lefties and righties is a bit of an oversimplification. Hitters have different strengths. Some can't hit spin. Some struggle with velocity. That's usually true, regardless of handedness.

"It's hard to put them all into one group," Stammen said. "There are certain lefties I know I'm not a great matchup for. There are other lefties I think I'm a really good matchup for. ... It's more matchup based. Usually a lefty vs. a lefty is a good matchup, but it's not all the time. We've got guys that can get both sides out. Pierce's curveball -- it's not like he can't throw that to lefties."

The Padres, of course, have options if they want to carry another left-hander in their 'pen. The offseason isn't over yet, and there are still lefties on the market. They also brought Ian Krol and Travis Bergen to camp as non-roster invitees. Ray Kerr, who arrived from Seattle in the Adam Frazier deal, is an option. The Padres would prefer that Ryan Weathers be built as a starter, but he could also serve as a length left-hander out of the 'pen.

"If a couple of these lefties have good camps, there's another spot for them with 28 men," Melvin said, noting the expanded rosters for April. "That's something we'll seriously consider."

3 Who's in? (And who helps cover the innings?)
The San Diego bullpen is going to get quite a test over the first couple weeks of the season. The Padres open with 14 games in 14 days, and they're likely to have a pair of starters -- Blake Snell and Mike Clevinger -- on workload limitations.

To that end, there's a possibility the Padres employ a planned piggyback day, Melvin said. That could be, say, Nick Martínez in relief of Snell or Weathers in relief of Clevinger.

"There's probably going to be at least one guy that's going to be able to give us some length," Melvin said of his 'pen.

As things stand, these are the locks for that bullpen: Pagán, Suarez, Stammen, Hill, Johnson, Lamet, Luis García and Austin Adams. Two spots are open. A long man, perhaps Martinez, has one. Maybe a lefty gets the other (though righties Nabil Crismatt and Steven Wilson are intriguing options).

Melvin is quick to note that these decisions don't need to be made on March 27.

"All of these are hypotheticals right now," Melvin said. "We still have some time left, and every day seems to change your mind a little bit. Most of this is going to come together toward the end, because we want to give a fair evaluation to the guys that we're looking at.”