Deep stack K_s band image from the VVV survey (Minniti et al. 2010). Location of the two counterparts (labeled a and b in the picture with respective uncertainties indicated by circle radii) suggested by Gosling et al. (2007) with X-ray positions of GRO J1744–28, reported by Wijnands & Wang (2002), and in the CSC 2.0 catalog (blue), the 4XMM-DR9 catalog (thin red lines), and as obtained in this work (thick red line). The white contours indicate 1 − 3σ confidence levels from the joint fit of all aforementioned X-ray positions obtained as described in the text.