The brother of St. Louis outfielder Chris Duncan and son of Cardinals pitching coach Dave Duncan, Shelley was moved off the 40-man roster last week to make room for first baseman Mark Teixeira, who finalized a $180 million, eight-year contract.
Duncan batted .175 with one homer and six RBIs in 57 at-bats last year for New York and .243 with seven homers and 27 RBIs for Scranton. He separated his shoulder making a diving catch on July 1 in the minors, missed about a month and didn't return to the majors.
Duncan was among 20 invitees the Yankees announced Wednesday. Among them were former AL Rookie of the Year Angel Berroa. Joining the infielder were pitchers Jason Johnson and Sergio Mitre, and catcher Kevin Cash.
The group of minor leaguers invited to major league spring training included pitcher Kei Igawa, outfielder Austin Jackson, reliever Mark Melancon and catcher Jesus Montero.