  ESO 137-G006 is the brightest cluster galaxy (BCG) of the cool-core and
dynamically young Norma cluster. We discover an atomic hydrogen (HI) absorption
line associated with this BCG using the Australia Telescope Compact Array. We
estimate a gas column density of $ \approx (1.3 \pm 0.2) \times
10^{20}\,T_{\rm{spin}}$ atoms cm$^{-2}$ with spin temperature, $T_{\rm{spin}}
\leq 194$ K, consistent with the HI properties of other early-type galaxies and
cool-core cluster BCGs. The relationship between the presence of cold gas and a
cluster cooling flow is unclear. Our results support the scenario that ESO
137-G006 may be a recent arrival to the cluster centre and not the original
BCG. This scenario is consistent with the observed spatial alignment of the
BCG's wide-angle tail radio lobes with Norma's X-ray sub-cluster and the
significant line-of-sight velocity offset between the mean velocity of Norma
and that of the BCG.
