Pari gbolohun ti o tẹle: Igbesẹ ti De Leeuw ni agbaye ni o wa ni akoko 1973-74. Omije akọkọ rẹ ni ISU Championship ni fadaka ni 1974 European Championships ni Zagreb, lẹhin Christine Errath. Níbi tí
1974 World Championships ni Munich, o gba ami ẹyẹ idẹ ati ki o tẹ lori podium pẹlu Errath ati Dorothy Hamill.