But like I said.. Even in that case, he would still only shut down the underneath OR over-the-top options. There's no way he can do both, nobody in the NFL is fast enough to do that. So it's not possible for one man to shut down an entire half of the field.
And like I said, he can only cover one man. If two guys slide to his area, one of them is going to be open even if Nnamdi is in zone coverage in that area. He would have to run with one of them and leave the other one alone. Nobody can shut down an entire half of the field by themselves.