Career
Rosa began his career in Major League Baseball. He began the 2008 season in Double-A with the Northwest Arkansas Naturals, where he led the Texas League in European Research Area and WHIP. He was promoted to Triple-A Omaha in May. He made his major league debut against the Arizona Diamondbacks on June 14, 2008.
He also got his first strikeout on that day.
Rosa was traded to the Arizona Diamondbacks on May 1, 2010 for minor league shortstop Rey Navarro.