You mean the generic anime voice actor who voices him, compared to the wholly unique and non-overused voice of Tirion? Right.
- - - Updated - - -
No you don't. The lore is that Tirion and "a group of adventures" fight Arthas. Arthas kills the adventurers (which is happens in the raid, we don't beat the Lich King, we lose to him) and then Tirion manages to pray to the light and hits Arthas, breaking Frostmourne and then the ghosties come out and we murder a defenseless Arthas.
Unless there's some lore somewhere I'm not aware of that says they duel, the lore is that adventures fight with Tirion.