Kyle Schwarber is still only 24, at least for a few more weeks until his birthday on March 5. He's younger than half of the six players who were finalists for 2017's Rookie of the Year awards. But despite his youth and relative inexperience -- even now, he's played in only 200 regular-season games -- his story already has more chapters written than plenty of players far older than he is.
After all that's happened, all the ups and downs, it's still somewhat unclear what Schwarber's future will be. But since winter is ending and Spring Training is nearing, let's try to take the optimistic view. What's the most likely outcome for the best version of Schwarber?
Before we look ahead, let's look back, just to remind you that so much has happened to Schwarber in the three-and-a-half years since he was drafted out of Indiana.
2014:No. 4 overall pick, ahead of Aaron Nola, Michael Conforto, and Trea Turner
2015: Second-half slugging sensation (.246/.355/.487, 131 wRC+), plus five October homers
2016: Devastating April knee injury before miraculous World Series return
2017:Sent back to Minors in June after first-half struggles; strong second-half slugging
All of the variation here is why projection systems are somewhat lukewarm on Schwarber, because the consistency just hasn't been there. Steamer, for example, projects Schwarber to hit .241/.341/.487 this year, a 114 wRC+ (where 100 is league-average). That's more good than great -- Neil Walker and Mike Moustakas also had a 114 wRC+ last year, for example -- but it's also basically what he's done to date, as his career line is a similar .222/.329/.471 (112 wRC+).

But due to his youth, and his prospect pedigree, and the fact that he did have to recover from that serious knee injury, let's take the best-case approach. Let's look at what he did over 225 appearances after he returned from the Minors last year, when he hit .255/.338/.565 (131 wRC+).
Let's say that's the "real" Schwarber, which may not be unreasonable because even that stretch came with a high 33.3 percent strikeout rate, and it's the exact same 131 wRC+ he put up in 273 plate appearances as a rookie in 2015. You should never just ignore the data you don't like, but remember, we're looking for best-case here. (Which is important; 84 percent of the 225 plate appearances he had after he returned came against righties, and his overall line would likely have looked worse if he'd played full-time against lefty pitching.)
There are a few ways to do this, really. Let's try it several ways based on the data available.
First, let's go find comparables based on outcomes. We need to find hitters who piled up at least 500 plate appearances through their age-24 seasons, and who were between 20 points and 40 points better than league average at the plate (in terms of OPS+) in that time. We need them to be lefty; we need them to have spent at least 80 percent of their time in an outfield corner, first base, or DH, as the latter two could be in Schwarber's future if he were to be traded; we need them to be worth five or fewer fielding runs, per Baseball Reference, which is to say "not a strong defender."
We did that, going back to the start of divisional play in 1969, and we came up with 15 names, and the results are fantastic, because they show how many different ways the best-case version of Schwarber could go:
Willie Aikens
Sean Casey
Chris Coghlan
Alvin Davis
Adam Dunn
Prince Fielder
Freddie Freeman
Ben Grieve
David Justice
Steve Kemp
Carlos May
John Mayberry
Gene Richards
Darryl Strawberry
Joey Votto
Of the 15, there are a few legitimate superstars in here. Votto and Freeman are in the midst of excellent careers and have become better defensive first basemen than they were initially. Fielder went on to have some monster power seasons, though he added limited defensive value and was finished due to injury at 32. Strawberry's trajectory was affected in part by off-field issues.
You might also include Justice or Casey, who made three All-Star teams apiece, or May, who made two All-Star teams, or Mayberry, a valuable part of Kansas City's strong 1970s rosters. Dunn may be the most interesting comparison: A powerful lefty with good on-base skills, huge strikeout numbers and limited defensive value in left that forced him to first and DH.
There were less encouraging outcomes, too. Grieve, Kemp, Aikens, Davis, and Richards were all essentially done by 30. Coghlan, briefly Schwarber's Chicago teammate, had a 500-plate appearance season just once after his rookie year. Stardom isn't guaranteed.

So there are a lot of ways that could go. Let's do it another way, too. We'll have to stick to more recent years for this, but let's look at similar players over the last decade in terms of "young hitters who have had big contact issues," particularly in the strike zone, as Schwarber has had. As it turns out, Schwarber's career contact rate on pitches in the zone (77.8 percent) and what he had when he was raking at the end of 2017 (77.2 percent) is nearly identical, so we don't even need to "best case" it. This might be who he is.
The data on this goes back to 2008, and in that time there have been 197 players who have had 500 plate appearances through their age-24 seasons. This group averaged an 87 percent contact rate on in-zone swings, and you'll find Schwarber appearing within the bottom 10 of that group.
Lowest contact rate on in-zone pitches, since 2008, through age 24
69.3 percent -- Joey Gallo
70.3 percent -- Mark Reynolds
75.4 percent -- Chris Davis
75.4 percent -- Oswaldo Arcia
77.0 percent -- Cody Bellinger
77.8 percent -- Schwarber
77.9 percent -- Wladimir Balentien
78.1 percent -- Michael A. Taylor
78.1 percent -- Miguel Sano
These are totally different names, by design, but we see the same wide variety of outcomes. Bellinger, Gallo, and at times Sano are some of the best young sluggers in the game. Davis and Reynolds are veterans who have struggled with consistency, combining for 548 homers but posting subpar seasons as often as great ones. Balentien and Arcia quickly washed out of the Majors; Taylor is a different situation entirely because he's also a good center fielder.
The takeaway from this is that there remains a great deal of uncertainty, even if we're only looking at the bat. Schwarber could be a star, or he could have a few nice seasons that don't go beyond that. He'd almost certainly be more valuable at first base or designated hitter than playing the outfield, which is part of why we suggested the Cubs trade him for pitching right after the World Series in 2016.
Schwarber's most likely outcome might be someone like Davis, or Dunn, who were huge power hitters with big strikeout totals to match. Maybe he'll have some Fielder seasons in him. Maybe he's the next Grieve. There are so many ways this could go.