After six years of steady but unspectacular progress in the lower ranks, Tamaasuka was promoted to the second highest "jūryō" division in November 2004 after winning the "makushita" championship with a perfect 7-0 record. In his "jūryō" debut he scored eight wins against seven losses by winning and then losing on alternate days, an oddity not seen in the top two divisions since 1988. He reached the top "makuuchi" division in the Nagoya tournament in July 2005, making his debut alongside Hakurozan. He was the first wrestler from Nagoya to reach the top division since Tochitsukasa in 1981.