  The latest experimental measurements of the hyperfine splitting
$E_{\rm{hfs}}=M_{\Upsilon(1 S)}-M_{\eta_b(1 S)}$ done by the Belle
collaboration and the perturbative and lattice QCD predictions show a tension
with the current extraction within lattice non-relativistic QCD. In this talk
we revise the analysis of radiative corrections to the bottomonium hyperfine
splitting within lattice non-relativistic QCD at the next-to-leading order. The
result of the analysis is in good agreement with the perturbative and lattice
QCD result as well as the direct measurement.
