Spejlsgaard qualified for the Danish squad in the women's 10 m air rifle at the 2004 Summer Olympics in Athens. She managed to get a minimum qualifying score of 396 to secure an Olympic berth for Denmark in her pet event, after finishing outside the final in ninth place at the Worlds two years earlier in Lahti, Finland. Spejlsgaard shot a decent 388 out of a possible 400 to tie for thirty-third place with Belgium's Daisy de Bock, Egypt's Shaimaa Abdel-Latif, and host nation Greece's Maria Faka in the qualifying round, failing to advance further to the final.