While Mother Nature continues to treat the Midwest like a Josh Hader fastball on the inner half of the plate, the Milwaukee Brewers have escaped to Arizona to kick off the 2019 campaign.

The Crew will return to Wisconsin for Opening Day at Miller Park with its 25-man roster intact, but over the next six weeks, the defending NL Central champions have several questions to answer and new faces to integrate.

Here are five pressing questions as the Brewers’ pitchers and catchers report to spring training.

1. What to expect from Jimmy Nelson in 2019?

Two years ago, a 28-year-old Nelson was in the midst of a career season. Among all National League starters, he ranked fourth in wins above replacement (4.8), eighth in ERA (3.49), sixth in strikeout rate (10.2) and eighth in walk rate (2.5), all culminating in a ninth place finish in Cy Young voting.

But when a wayward slide in early September of that same season resulted in a right rotator cuff strain and a nasty labrum tear, Nelson underwent surgery and was sidelined for the entirety of 2018.

This week, Nelson took another step towards a return by throwing a 45-pitch bullpen session without any setbacks. Baseball history is littered with pitchers making failed comebacks after labrum injuries, but with nearly 19 months between the date of the injury and Opening Day this year, the Brewers have afforded Nelson more recovery time than past labrum victims. Milwaukee’s incredible pitching depth will also allow the organization to be even more careful with Nelson. The Brewers are not relying on Nelson for 200 innings; anything more than a replacement-level performance this year will be gravy.

2. What impact will Yasmani Grandal have on the pitching staff?

The Brewers inked Grandal to a one-year deal with a mutual option for 2020 during the offseason, but even if it’s only a one-year layover, he could still have an outsized impact on the pitching staff this season. Grandal is widely regarded as one of the best catchers in the game at stealing strikes, a notion that is backed up by Baseball Prospectus’ framing runs stat. Grandal has finished inside the top five in framing runs in each of the past four seasons and posted the top overall mark in 2018.

Milwaukee’s starters compiled a 3.92 ERA last year, and while that was good enough for 11th in baseball, that number was partially masked by luck and Craig Counsell’s quick hook. If Grandal can turn a few balls into strikes every night, the Brewers’ starters will be able to avoid hitter’s counts, extend their outings, and lessen the wear and tear on the Counsell’s talented bullpen.

3. Will the bullpen’s three-headed monster be able to post a repeat performance?

Speaking of said bullpen, will its three linchpins – Jeremy Jeffress, Corey Knebel and Hader – be able to continue last summer’s run of dominance? Hader led all NL relievers in innings pitched, with Jeffress not too far behind in eighth. Knebel also was among the league leaders in innings over the second half of the season, and then all three combined to throw 28 frames in the Brewers’ run to Game 7 of the NLCS.

Year-to-year relief performances are notoriously volatile, especially in seasons following heavy workloads. Counsell rode his bullpen incredibly hard down the stretch run, and while that proved to be the right call, it’s unlikely he can do that for a second consecutive season. Hader clearly wore down in the second half (3.78 ERA after the break compared a 1.50 ERA prior), and Jeffress struggled mightily in the postseason (6.75 ERA).

The Brewers will have to walk a fine line in the regular season this year; Counsell will be forced to use his top bullpen talent to close out games in the increasingly competitive NL Central, but he also needs to save some bullets for the playoffs. The success of the starting rotation could have the biggest impact on Milwaukee’s long-term relief success.

4. What's going to be the starting rotation?

Jhoulys Chacin should nab the Opening Day start – prayers up for whomever takes on the Brewers’ Opening Day curse next – though he would be more well-suited as a No. 2 or 3 starter in the typical rotation for a contender. But despite the lack of top-end talent, the Brewers staff features more major-league depth than maybe any other team in the sport.

Chase Anderson, Zach Davies, Brandon Woodruff, Corbin Burnes, Freddy Peralta, Junior Guerra and the aforementioned Nelson all have varying degrees of starting experience, and while they all have their warts, they also all have put together quality seasons in the not-so-distant past. Brent Suter could also play a role down the stretch as he recovers from Tommy John surgery last July, and the Brewers recently signed former Cleveland starter Josh Tomlin to a minor-league deal.

Barring a trade or an injury, the initial five-man rotation seems likely to include Chacin, Anderson and Davies. If Nelson proves healthy, he’ll grab that fourth spot, creating a battle between Woodruff, Burnes and Peralta for the final opening. Peralta flashed big-time stuff with a gaudy strikeout rate last summer before fading; Burnes dominated in a bullpen role after his call up but did struggle as a starter in Triple-A prior to joining Milwaukee; and Woodruff likely has the highest floor of the three in 2019, though he is yet to prove capable of pitching deep into ballgames across any level.

Woodruff’s consistency may earn him the nod to start the year, but Peralta and Burnes will certainly be heard from at some point in 2019, potentially in both relief and starting roles.

5. What’s available on the transaction market?

The Brewers have largely eschewed the pitching market so far this winter, though they have been connected to some big names. Dallas Keuchel is the top free agent arm available, but there has been nary a peep about where he may land, even as spring training gets rolling across baseball. Keuchel was reportedly asking for a six- or seven-year deal approaching $30 million annually, and though he will undoubtedly fall short of those goals, the Brewers are likely wary of lengthy free agent deals for starters after previously whiffing on Jeff Suppan and Matt Garza. The Brewers have been "loosely" linked to Keuchel, but an agreement may only come to fruition if Keuchel signs a one-year pillow contract a la Grandal.

Milwaukee was also connected to longtime San Francisco ace Madison Bumgarner – who still has one year worth $12 million on his deal – in trade rumors, but as the season draws nearer, any MadBum swap becomes more and more unlikely. The Giants are also the latest team to kick the tires on Bryce Harper, so they probably are not looking to undergo a Miami-style sell-off right now.

The Brewers have the pieces and the cash to make a move, but unless a favorable deal falls into general manager David Stearns’ lap, this is the team that the organization will go to war with this summer.