Cika wannan jumla: Gravalos ya yi takara don
maza 4 × 400 m relay a Wasannin Olympics na 2008 a Beijing, tare da abokan wasansa Stylianos Dimotsios, Konstadinos Anastasiou, da Pantelis Melachroinoudis. Ya gudu a mataki na biyu na zafin jiki na biyu, tare da lokacin raba mutum na 45.66 seconds. Tawagar ta gama tseren a matsayi na goma sha biyar don mafi kyawun lokacin kakar wasa ta 3:04.30, ta kasa ci gaba zuwa wasan karshe.