About a year-and-a-half has passed since the Boston Red Sox gave Rusney Castillo a seven-year, $72.5 million contract, and he’s still a riddle with mystery and enigma coverings.

But maybe not for much longer. Castillo has star potential in him somewhere, and he’s finally in a position to let it out in 2016.

The Red Sox are looking pretty good heading into the new season. After adding David Price, Craig Kimbrel and others to a core group that played pretty well down the stretch in 2015, we’re thinking the Red Sox will party like it’s 2013 and go from worst to first once again. That may even undersell their potential, as FanGraphs projects the Red Sox as the American League‘s best team.

But perfect, the Red Sox are not. Their rotation beyond Price doesn‘t impress much. Pablo Sandoval and Hanley Ramirez are coming off terrible 2015 seasons. Dustin Pedroia is 32 and coming off two straight injury-marred seasons. David Ortiz is on the wrong side of 40 heading into his farewell tour.

It’s Castillo, though, who’s arguably the biggest question mark of them all.

The 28-year-old Cuban outfielder looked like a star in the making when he broke through with a .928 OPS in an impressive 10-game cameo in 2014, but 2015 saw him battle injuries and ineffectiveness. He played in only 80 major league games and hit just .253 with a .647 OPS.

The projections don’t have high hopes for Castillo in 2016. According to FanGraphsZiPS and Steamer have him pegged for less than a full season of work and for less-than-awesome production:

There’s nothing unfair about this. Castillo has had a rough go of it so far and, at 28, he’s not an up-and-coming prospect. One is obliged to entertain the possibility that maybe his shortcomings are permanent.

But enough pessimism. We’re here for optimism! And for pretty good reasons!

If nothing else, one thing Castillo has now that he didn’t a year ago is a clear opportunity with the Red Sox. Whereas he was merely in a position to earn a starting gig going into spring training last season, this year, the starting left field job is his to lose.

Are the Red Sox taking a chance by betting on Castillo? Sure. But are they also betting on a guy with some pretty good natural talent? Yeah. And they already know some of his talent can translate to the majors.

As Ben Badler of Baseball America wrote before Boston signed Castillo in August 2014, scouts who saw him play in the Cuban National Series knew he could at least be a good defender thanks to his plus-plus speed and strong instincts.

Albeit in just a 90-game sample, Castillo has been more like a great defender. The defensive metrics tell us he played above-average defense in his first taste of the majors in 2014 and way-above-average defense in 2015. Despite playing a little more than 700 innings in the field, he racked up more defensive runs saved than all but six other outfielders. 

What surprised scouts back in August 2014—and which was presumably instrumental in getting Boston’s checkbook out of its pocket—was just how much power Castillo had. He was known more as a line-drive hitter in Cuba, but suddenly there he was with 20 extra pounds of muscle packed onto his 5’9″ frame. That led to plus raw power in batting practice.

And on occasion, it’s led to impressive power displays in games. Like so:

Close your eyes, light a candle and put on some soothing music, and you’ll be able to imagine Castillo as a slick-fielding outfielder who also hits a bunch of dingers. These types are otherwise known as really good players, a notion that surely has the Red Sox crossing their fingers.

But there’s a gap Castillo has to bridge in order to get there. As you’ve probably already guessed, it has to do with his offense.

Castillo’s plus raw power is nice, but there are good reasons why he’s only hit seven home runs and racked up a .379 slugging percentage in his 90 major league games. His better-than-average career strikeout rate can vouch that he’s not totally overmatched against big league pitching, but he’s had issues making good contact.

That’s most noticeable in his career ground-ball percentage, which is north of 60. Dan Farnsworth of FanGraphs has some insight into that, as he noted in September 2014 that the swing Castillo brought to the States had “little natural lift.” He has a flat swing that certainly would produce so many grounders.

As Badler noted in 2014, scouts also saw the length of Castillo’s swing as a problem. That helps explain the other thing that’s holding him back: struggles against good velocity.

According to Baseball Savant, Castillo hit just .203 on anything over 93 mph in 2015, with all of his hits being singles. That’s compared to a league-average .258 batting average and .403 slugging percentage.

And so, we have the following Sherlockian deduction: To reach his offensive potential, Castillo needs to adjust his swing so it’s quicker and with more lift.

And that, in turn, leads us to the good news: He knows this.

Brian MacPherson of the Providence Journal reported last August that Castillo was already working on making adjustments to his swing that would allow it to be shorter and more direct to the ball. Recently, August Fagerstrom of FanGraphs looked to see what kind of changes were made and found that Castillo’s swing seemingly did gain a bit more loft.

If Castillo can hold on to that, all he needs to do next is make his swing shorter. As MacPherson reported recently, that’s how Castillo has spent his offseason:

This shouldn’t be mistaken for proof that Castillo has his swing figured out. But because he’s already pinpointed the weaknesses he needs to correct, his swing is a work-in-progress deserving of high hopes. With the concepts nailed down, getting his swing where it needs to be could be as simple as getting enough reps to get into a rhythm.

Of course, this means Castillo needs to do another thing he had trouble doing in 2015, and that’s stay on the field. Starting with an oblique setback in spring training and continuing with shoulder, foot and quad ailments, the injury bug gave Castillo a hard time last year.

In an interview with Scott Lauber of the Boston Herald, Cuban baseball expert Peter Bjarkman expressed doubt over whether Castillo will be able to put his injuries behind him. He’s coming from a Cuban system where off-the-field workouts aren’t as closely monitored as they are in the major leagues and where the culture pushes players to play through injuries.

“It doesn’t surprise me that he’s had injuries,” said Bjarkman. “Now, the question is, is he going to be able to play regularly now in his career, because maybe playing down there has taken a toll on his body and he’s not the same player that he was two, three, four years ago?”

But while this is a fair question, Castillo’s 28 years hardly make him ancient by baseball standards. Between that and the fact that the Cuban National Series plays a shorter season than Major League Baseball, it may be a stretch to think Castillo’s body is wrecked beyond repair.

And according to the man himself, he now has a much better idea of how to get his body ready to last for a 162-game season. As he told Lauber, he used 2015 as a learning experience and altered his offseason training program accordingly.

“I tried to focus a little bit more on a different style to cope with [being worn out and hurt] in the future,” Castillo said through a translator. “I know what it takes to take a toll of the games. I’m preparing hard and [for] what it will take physically, so I’m prepared from now on and I’m ready to face that challenge.”

All this puts Castillo in a much different place than he was a year ago. He was coming off a promising breakthrough, sure, but all he really had to follow it up was his raw talent. Now he has his raw talent, better physical preparation and a better idea of what kind of adjustments he needs to make.

This should help clear up the shroud of mystery that still surrounds Castillo. And once it’s gone, the star player the Red Sox thought they were buying in 2014 may finally emerge.


Stats courtesy of Baseball-Reference.com and FanGraphs unless otherwise noted/linked.

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