Sierra (shoulder) will begin the season at extended spring training, J.P. Hoornstra of the Los Angeles Daily News reports.
Sierra is working his way back from a shoulder injury that forced him to miss all of last season. Farm directer Will Rhymes said the 27-year-old is "coming along," though he declined to offer up a timetable for Sierra's return. Once healthy, Sierra will likely report to Triple-A Oklahoma City.