For one, I think Naruto was protecting his hand a la Sakura because it is not same to touch the black rod with bare hands. However, since he can kick the black ball, he could be absorbing chakra in that panel. This is a bit suggested by the way he looked at his had after the action.
Should we be surprised to see Naruto absorbing chakra?
My guess is no. Actually, if you can give, it means you know the , mechanism of how it flow and you can take it back. Maybe it is not accurate, but I can check on how Naruto absorb chakra of biju in his inner world. This has to be the same absorption techs and I said it before - that is Naruto was not absorbing because he had no interest in doing it.
Moreover, Hashirama could absorb as well and all his jutsus could do the same. In case you forgot, Naruto has the same source as Hashirama. Plus, remember the absorption Rasengan, etc.