 Weir's stay at Tynecastle was brief and he moved to St. Johnstone within a year, signed by Paul Sturrock in a swap deal that saw Colin Miller move in the other direction.He ruptured his Achilles tendon during the final game of the 1997/98 season, which ruled him out of most of the following season.He returned to the starting line-up, as a right-back, on 4 April 1999, against Rangers, and scored the first of Saints' three goals in a 3–1 victory.