  The recent observation of superconductivity in Nd$_{0.8}$Sr$_{0.2}$NiO$_2$
has raised fundamental questions about the hierarchy of the underlying
electronic structure. Calculations suggest that this system falls in the
Mott-Hubbard regime, rather than the charge-transfer configuration of other
nickel oxides and the superconducting cuprates. Here, we use state-of-the-art,
locally-resolved electron energy loss spectroscopy to directly probe the
Mott-Hubbard character of Nd$_{1-x}$Sr$_x$NiO$_2$. Upon doping, we observe
emergent hybridization reminiscent of the Zhang-Rice singlet via the
oxygen-projected states, modification of the Nd 5$d$ states, and the systematic
evolution of Ni 3$d$ hybridization and filling. These results clearly evidence
the multiband nature of this system and the distinct electronic landscape for
infinite-layer nickelates despite their formal similarity to the cuprates.
