If they're both invulnerable, then how do you expect a winner?

I am trying to imagine Doomsday playing boxing.🥊🥊

Noone wins this. And if someone does, noone will be around to witness it.

@Leostales Kryptonians are invulnerable, but when they fight they can harm eachother. It is probably the same in this case.

"but when [Kryptonians] fight they can harm eachother"

Then they aren't invulnerable.

Neither of them are actually invulnerable but Damage hits harder.