The other thing I will offer up is that in reality you didn't have enough lens on the subject, so cropping this photo to a desired size for artistic reasons is going to exacerbate the noise perception. (you are looking at the face at 100% and seeing the noise that lives there, in the shadows as it were)
I.e. there is a ton of blank space on this image so you are going to want to crop it for artistic reasons. In an ideal world we'd all have 800mm lenses for these situations (or seats twice as close!) and increase the exposure here even more so as to draw the face with more photons. It looks like you were pretty much at the limit of everything here, I'm guessing shooting at full zoom of 400mm, and you were already wide-open at f/4. About the only other thing you could have done, and it would be a compromise is go one shutter speed slower.
Anyhow, a good lesson on why even with a D4, if we are shooting at high ISO, we had better get a tight crop right in camera if at all possible. Tough situation!