PITTSBURGH -- It has snowed and snowed in Pittsburgh over the past week, so it’s somewhat comforting to think about the warm Florida sun soon approaching as Spring Training is less than a week away.

So here’s my first edition of the Pirates Inbox as we get set for Grapefruit League action and the position battles start to heat up.

Do you think Mitch Keller has a breakout season, and who do you think will be the "ace" of the starting rotation?
-- @BucsfanNY

Keller told our outgoing Pirates beat reporter (and new Rays reporter) Adam Berry last year: “One day, I want to be the ace.”

When he began his pro career, he was consistently in the top tier of the Pirates’ prospects. Now, he’s an MLB pitcher who has graduated from prospect status. His first taste of the Majors was not ideal (38 earned runs in 48 innings), and even as he saw big gains in 2020, he had to work overtime to get batters out. But Keller still has only 69 2/3 big league innings -- not even a full half-season’s worth, in most cases -- under his belt.

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I know this may be obvious, but it’s worth repeating: Being a top prospect does not mean things will come easy or quickly. In fact, prospects are often evaluated by their potential ceiling, and that’s especially the case with high school pitchers like Keller. Let's not rule out Keller being a future top-end starter for the Pirates based on early results.

What I can say is that if Keller is going to establish himself as the up-and-coming ace of the up-and-coming Pirates, the season to prove that is 2021. We know he will get every fifth day (or near it). We know he will be given length in games to work himself out of trouble.

For now, my prediction for the “ace” of the 2021 rotation is not Keller. My guess would be Steven Brault. I know, I know: Picking the regular starter with the lowest ERA last season isn’t the boldest pick. But the way his pitches move and his strides to unify his delivery last season made for a stellar final month, and I think it points to increased success.

What will the projected starting rotation be?
-- @mrsblackngold

Any chance Cody Bolton makes the rotation out of Spring Training?
-- @BurghSportsFan72

We’re still unsure if the Pirates could make a rotation depth acquisition, but here’s where it stands for now:

Steven Brault
Chad Kuhl
Mitch Keller
JT Brubaker
Cody Ponce

My guess of Ponce is based on a solid showing in his first five MLB games, including three starts, as he posted a 3.18 ERA. However, the Pirates could easily turn to Wil Crowe, their No. 21 prospect per MLB Pipeline. He had a rough go in his first three Major League starts (13 runs/11 earned runs in 8 1/3 innings) but is due for a longer look.

There's also a good chance Miguel Yajure, the Bucs' No. 14 prospect per MLB Pipeline, will be given starting reps and could fairly soon end up as the fourth or fifth starter. He's made three solid relief appearances in the Majors already. Roansy Contreras (No. 19) is on the 40-man roster and could get a callup some time this year.

I don’t believe Bolton, Pittsburgh's No. 13 prospect, will make the rotation out of Spring Training, mainly because he didn’t show great results in his short time at Double-A. There isn’t a need to get him to the Majors, so a season beginning at Double-A wouldn’t surprise me, though I think Triple-A is a possibility to begin the year.

How soon until Oneil Cruz is on the MLB club roaming SS everyday?
@Mike_InIllinois

The good folks at MLB Pipeline have Cruz, the Pirates' No. 3 prospect, listed as an ETA of 2022. Now, does that mean he won't arrive this year? Not necessarily. We all know the raw tools Cruz possesses, and we'll need to keep a close eye on Triple-A Indianapolis to see how they play there.

However, he won't be roaming at shortstop for the Pirates every day this year; in fact, some evaluators still aren't sure he'll stick at shortstop despite his ability to field the position well. His exceptional arm make him a fit at other positions -- just imagine his throws to the plate from right field at PNC Park -- but outside of third base, the organization has kept him squarely at shortstop in his development.

If he stays at shortstop and translates what he did in 2019, when he recorded a .831 OPS in 73 games across three stops, to the Majors, I think late 2022 to '23 would be the window you're looking at. But Kevin Newman and Cole Tucker could also establish themselves and force the Pirates to be creative.

What’s the next step and realistic expectation for Travis Swaggerty this year?
-- @kyle_sutphin

Swaggerty’s jump to Class A Advanced in 2019 did not start the way the Pirates had hoped, but he polished his mechanics and that showed in the second half of the season, when he batted .306/.375/.430 with 15 doubles, a triple and four homers in 63 games. Swaggerty’s good speed and fielding ability have been consistent, so it's showing sustained strides at the plate that will allow him to climb.

The former first-round Draft pick, who is ranked as the club's No. 7 prospect, could start the year at Double-A Altoona, although it wouldn't be a slight to send him back to Bradenton to begin. There’s no rush to get him close to the Majors since the Pirates added Major League-ready depth in the outfield with Anthony Alford, Brian Goodwin and Troy Stokes Jr. over the past calendar year.