Castillo was off to a solid start in Triple A Pawtucket, going 5-for-12 with a double, walk, and steal in the first three games of the minor league season before his injury. In his brief time since signing a seven-year, $72.5 million deal with the Red Sox last August, he’s been a consistently productive player who has nonetheless had a difficult time staying on the field due to a succession of health issues.

Red Sox outfielder Rusney Castillo, after a Monday exam in Boston on a shoulder that he injured in an attempt to make a diving play on Saturday, will land on the disabled list to let the injury rest and heal. Manager John Farrell is expected to offer more precise details regarding the nature of his shoulder injury later Tuesday, but multiple major league sources describe Castillo’s prognosis as encouraging, suggesting that worst-case scenarios (such as surgery to repair a tear) appear unlikely to come to fruition at this time.


Indeed, it was in part because of injuries – a thumb injury that cut short his Arizona Fall League season and delayed his arrival in the Puerto Rican Winter League, as well as an oblique strain at the start of spring training that prevented him from playing for the initial weeks of the Grapefruit League schedule – that the Red Sox optioned the 27-year-old to Pawtucket, despite a tremendous performance when on the field in spring training. Castillo hit .310 with two homers and four extra-base hits in nine games while playing excellent defense in center and right.

“The only thing he hasn’t done as a professional baseball player in the United States is play every day for a stretch of time. That’s the only thing he hasn’t been able to do, through no fault of his own, just through circumstance, and then he misses some time in the spring,” Sox GM Ben Cherington said when announcing the decision to option Castillo at the end of spring training. “He’ll have an opportunity to do that. We’re making a decision to give an opportunity to some other guys to start the season. He’ll have the benefit of being able to get into the season and play every day and hopefully get on a roll, and then we’ll see where it goes.”


For now, however, that opportunity is being interrupted. Castillo’s quest for regular playing time will have to wait.

His time on the sideline will redraw the Sox’ depth equation, particularly in center and right fields. Whereas Castillo likely would have been an option of first resort in case of an injury or struggle by either Mookie Betts or Shane Victorino, Jackie Bradley Jr., who is off to an excellent start in Pawtucket, is likely next on the depth chart until Castillo is ready to play on a regular basis.

Alex Speier can be reached at alex.speier@globe.com. Follow him on twitter at @alexspeier.