Orioles minor league prospect Dariel Alvarez is expected to undergo Tommy John surgery after suffering an elbow injury while making the transition from the outfield to the mound, according to multiple sources.
Alvarez was persuaded by the club to concentrate on pitching when it became apparent he was too far down the outfield depth chart to reach the majors with the O's this season.
He was initially reluctant, but eventually agreed to the switch when he got some assurances that he would still be able to work out in right field and continue to hit.
He had pitched some during his career in Cuba, and a live arm said to possess a mid-90s fastball has intrigued the Orioles for the past couple of years. The club believed moving him to the mound provided the best path to the majors for him in the organization.
The Orioles signed Alvarez to an $800,000 signing bonus -- a club record bonus for a Cuban defector -- in July of 2013, and many other clubs were interested in Alvarez as a pitcher.
But the Orioles groomed Alvarez to play outfield, and in his first full professional season in the U.S., he hit .306/.330/.472 with 15 homers and 87 RBIs between Double-A Bowie and Triple-A Norfolk.
Alvarez earned brief major league call-ups the next two years, but never differentiated himself as the impact outfield bat the club projected him to become. Last season, Alvarez hit a career-high 38 doubles at Norfolk but hit a career-low four homers.
The Orioles had success transitioning Mychal Givens from a position player to a reliever, and put Alvarez on the same throwing program after he was optioned to minor league camp in early March.
At the time, manager Buck Showalter said the club didn't want Alvarez to exhaust his minor league options before seeing if he could develop as a pitcher. But now, with Alvarez facing a projected recovery time of at least one year, his future with the club is in question.
Sun staff writer Eduardo A. Encina contributed to this report.