Who will be Opening Day starter for Brewers?

Center field also among questions heading into Spring Training

Who will be Opening Day starter for Brewers?

MILWAUKEE -- Here's a sign that Wisconsin's winter is almost over: Brewers baseball is back.

The club's pitchers and catchers report for Spring Training on Friday, though in reality many have been working out at Maryvale Baseball Park for days. Players will undergo physical exams on Saturday, typically off-site, before participating in the team's first formal workout on Sunday morning.

Those workouts are open to the public for free, offering fans, rosters in hand, an up-close opportunity to meet the club's slew of newcomers. The Brewers will have a new Opening Day starter on the mound and at four positions, minimum, many of whom were acquired in one of GM David Stearns' nine trades.

•  Prospects | Newcomers | Position battles | Bounceback candidates | Projections

Fewer than half of the players currently on the 40-man roster -- 17 of 39 -- were on the roster at this time last year. Beyond the 22 new players on the roster, the Brewers have 19 non-roster invitees vying for jobs, 15 of whom were not in the organization on July 15, 2015.

In other words, introductions will abound in Brewers camp, as will question marks. Here are three of the biggest questions that need answers before Opening Day:

1. Who gets the ball Opening Day?
Giants pitchers and catchers hadn't even formally reported for Spring Training when manager Bruce Bochy named left-hander Madison Bumgarner his Opening Day starter. That's the luxury of having an ace. The Brewers have no such pitcher, so manager Craig Counsell's choice to oppose Bumgarner will be interesting. Does he go with the veteran, Matt Garza, as a show of support and an olive branch after the contentious way Garza's season ended last year? Or Wily Peralta, who was the Brewers' most valuable pitcher in 2014 before an oblique injury hampered him last year? Or, if it's simply a matter of performance, how about Jimmy Nelson, who led the club last season in victories, innings and wins above replacement? Yes, it is a symbolic assignment. But it is also an opportunity for Counsell to give one of his pitchers a boost of confidence entering the long season.

Spring Training: Schedule | Tickets | More info

2. Who takes over center field?
Of the Brewers' not-quite-settled positions -- third base, shortstop and center field -- the latter is the most wide open. The Brewers traded away Carlos Gomez and Gerardo Parra in July 2015, and while they have some quality prospects at the position (Nos. 2-4 prospects Brett Phillips, Trent Clark and Tyrone Taylor among them), they do not have anyone ready to take over at the big league level. So Stearns claimed Kirk Nieuwenhuis off waivers from the Mets, traded with the Pirates for Keon Broxton, with the Mariners for Ramon Flores and with the Pirates for Rymer Liriano, and signed Eric Young Jr. and Alex Presley to Minor League deals.

Graves' 2016 Brewers predictions

3. Who will surprise?
It's one of former GM Doug Melvin's favorite mantras: Someone always surprises. Spring Training statistics are notoriously misleading, but this camp could nonetheless offer some clues about a breakout candidate for 2016, whether it be one of Stearns' many under-the-radar outfield acquisitions, a bounce-back candidate like Garza or Chris Carter or non-roster pitcher Chris Capuano, or one of the prospects getting a first taste of big league camp, like shortstop Orlando Arcia or Phillips or catcher Jacob Nottingham. Rebuilding means opportunities for players to open eyes, and it all begins on Friday.

Adam McCalvy is a reporter for MLB.com. Follow him on Twitter @AdamMcCalvy, like him on Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.