This secured the talented Wallace the Ulster Number 15 shirt for the next series of games including the 27–21 defeat of Edinburgh to lift the Celtic Cup, Ulster's first piece of silverware since the famous 1999 European Cup triumph, and the 33–0 thumping of Leicester Tigers at Ravenhill in January 2004, in the return leg of the Tigers' fixture though he had a torrid time playing at full-back and was relegated to the bench for the majority of the remainder of the season. Wallace had 3 more starts that season, twice at outside centre and once again at fullback, all due to injuries to other squad members. He was though successfully used as an impact substitute off the bench scoring a number of tries from here.