After experiencing some discomfort in his throwing shoulder, Marlins right-hander Anibal Sanchez underwent a precautionary MRI earlier this week, a source confirmed to MLB.com on Thursday. The ailment is not considered serious, and the 22-year-old Maracay, Venezuela, native hopes he'll be ready to begin throwing when the club reports to Spring Training on Feb. 17 in Jupiter, Fla. Sanchez was one of four Marlins rookies to make MLB history a year ago by posting 10 or more wins.