On 5 May 2003, Lyng won a second successive National League medal after lining out at midfield in Kilkenny's 5–14 to 5–13 defeat of Tipperary in the final. On 6 July 2003, he won his third consecutive Leinster Championship medal after scoring three points from play in the 2–23 to 2–12 defeat of Wexford in the final. On 7 September 2003, Lyng again lined out at midfield when Kilkenny faced Cork in the All-Ireland final. He scored a point from play and collected a second successive winners' medal following the 1–14 to 1–11 victory. Lyng ended the season by winning a second All-Star award.