Close view of the Chandra archival image (OBSID. 5055; 0.5–10 keV) around the core of NGC 6388. In the image, black circles correspond to all the Chandra sources detected so far in quiescence by Cseh et al. (position uncertainty 0.5 arcsec; 2010). The blue circle represents the COG of the GC (position uncertainty 0.3 arcsec). The improved XRT position determined in the present work is indicated with a red circle (see Sect. 2.3), and the Chandra position reported by Pooley et al. (2011) is represented with a green circle.