a) 2D LUCI1 spectrum of J0745+4734. Blue to red colours indicate increasing counts. Top and bottom correspond to north and south direction, respectively. The black solid lines indicate the apertures used for extracting the off-nuclear spectra. b) The integrated flux ratio of the shifted and systemic [OIII] components with respect to the BLR Hβ emission line detected in the “off-nuclear” spectra of J0745+4734 extracted from different apertures. Negative (positive) pixel values correspond to south (north) direction (1 pixel ~ 1.9 kpc at the redshift of J0745+4734). The yellow band highlights the presence of extended [OIII] emission. c) Maximum velocity of the shifted and systemic [OIII] components detected in the “off-nuclear” spectra of J0745+4734.