Graziano: Colts will see what Riley Leonard can give them in Week 18 (0:43)Open Extended ReactionsINDIANAPOLIS -- Philip Rivers' second act has come to an end. The Indianapolis Colts are turning to rookie Riley Leonard as their starting quarterback for Sunday's season finale at the Houston Texans, sources told ESPN, ending veteran Rivers' run after coming out of a five-year retirement. With 2023 first-round pick Anthony Richardson Sr. also on injured reserve from a previous injury, the Colts were left with few options. Coach Shane Steichen, one of Rivers' closest friends, coaxed Rivers out of retirement because of his intimate knowledge of the offense and leadership capacity. The prospect of Leonard starting on Sunday, Steichen said, "will be good for his development."