Final Prediction for Boston Red Sox's Key Spring Position Battles

Opening Day is less than three weeks away for the Boston Red Sox.  It won't be long before the final roster cuts are made and the club decides who will take the field against the Philadelphia Phillies on April 6.

Most of the Red Sox regulars were determined before spring training began.  Boston signed Pablo Sandoval and Hanley Ramirez to play third base and left field, respectively, while incumbent starters return at the other infield positions.

The Red Sox filled out their rotation by adding Rick Porcello, Wade Miley and Justin Masterson, and they retained the services of Koji Uehara as closer.

Not everything is decided, though.  There are two major position battles underway in Red Sox camp in Fort Myers, Florida: A pair of outfield spots are up for grabs, and the Opening Day starting pitcher has yet to be determined.  Here are predictions for both.

Center Field and Right Field

Heading into spring training, Rusney Castillo and Mookie Betts looked like the clear choices to join Ramirez in the outfield.  Boston spent $72.5 million on Castillo last year, obviously with the intention of making him an everyday player.  Meanwhile, Betts exploded onto the scene as a 21-year-old rookie in 2014.  He hit .291 with seven stolen bases in 52 major league games despite starting the season in Double-A.

However, Red Sox manager John Farrell threw a wrinkle into the plans in late February.  Via NESN's Ricky Doyle, Farrell said: "If Shane Victorino is fully capable and fully healthy, he's our right fielder."

The outfield situation became further complicated when Castillo suffered an oblique strain on March 3.  The 27-year-old has yet to take a spring training at-bat against major league competition.  Castillo was shut down for two weeks, then appeared in minor league games on Wednesday.

From Scott Lauber of the Boston Herald, Castillo said:

"

I was able to get out on the field and do everything I needed to. I didn't feel any pain in my oblique area. Overall it went very well. …

My goal is to be ready for that (opening) day, and that's what I'm training for. Hopefully if all goes well, I'll be ready that day. 

"

Victorino's spring isn't faring a whole lot better than Castillo's is to this point.  The 34-year-old missed a few days in early March after feeling some soreness in his legs from running the bases.  He's appeared in a total of six Grapefruit League games, going 1-for-13 with four strikeouts.

On the other hand, Betts is tearing the cover off the ball.  Over 29 at-bats, he has 13 hits, including five doubles and two triples—good for a .448 batting average and a .759 slugging percentage.

Tim Britton of the Providence Journal writes: "Betts has clearly separated himself in camp, and he probably will be the first Red Sox hitter to step into the batter's box in the 2015 regular season."

Prediction: Betts will start the year in center field, with Victorino in right field.  But don't expect things to stay that way for long.  As ESPN.com's Tristan H. Cockcroft notes, Victorino "began 2014 on the DL and has landed on the DL before Memorial Day in three of the past four seasons."  Look for Castillo to be a regular starter by the end of April.

Opening Day Starting Pitcher

This is a two-horse race between Clay Buchholz and Rick Porcello.  Buchholz is the veteran who's been with Boston his entire major league career, dating back to 2007.  Porcello is the Red Sox pitcher who put up the closest thing to No. 1 starter numbers last year, going 15-13 with three shutouts, a 3.43 ERA and a 1.23 WHIP over 204.2 innings.

Neither is an ideal choice, but one of them is going to get the ball on April 6 in Philadelphia.

Porcello pitched on Wednesday, giving up three hits, two walks and one run in four innings while also recording three strikeouts.  Via Sean McAdam of CSNNE.com, Farrell said the following about Porcello's outing:

"

(Porcello) had four good innings of work today. He was able to get his pitch count to the level we hoped to and continues to make strides as far as getting in shape for the start of the season. I thought he made a number of good pitches with men in scoring position. It was a solid day of work for him.

"

Porcello's exhibition numbers now stand at 10 innings pitched, three earned runs, eight strikeouts and a 1.30 WHIP.

Buchholz threw the day before, allowing two earned runs on five hits while striking out six in four innings.  From Steve Silva of Boston.com, Buchholz said afterward:

"

I feel pretty good actually. I trained pretty hard this offseason to come to camp somewhat ready and the training and everything's paying off being here. …

Overall, feel like arm's in good shape. Just gotta continue to work on some little minor adjustments throughout the delivery and hopefully all that comes together before the start of the season.

"

Buchholz's spring stat line reads 10 innings, two earned runs, 12 strikeouts and a 1.10 WHIP.  Both Porcello and Buchholz have thrown the ball well in Fort Myers, and neither has done anything to set himself apart from the other.

Farrell hasn't said which pitcher he expects to go with on Opening Day.  However, Buchholz has been pitching ahead of Porcello since the start of spring training.

Prediction: With both pitchers performing at a similar level in Grapefruit League play, the prevailing opinion from before the preseason still holds true—Buchholz will start Opening Day, with Porcello getting the nod in game No. 2.  Don't be the least bit surprised, however, if Porcello takes over the role of "ace" as the season progresses.

Mark Vandeusen is a Featured Columnist covering the Boston Red Sox for Bleacher Report.  Follow him on Twitter @LucidSportsFan. Unless otherwise noted, all statistics via RedSox.com and contract information via spotrac.com.