A search for Beyond the Standard Model (BSM) particles that decay into a pair of
jets is performed using 139 fb−1 of ATLAS pp collision data recorded from the Large Hadron Collider operating at √s = 13 TeV. To increase the sensitivity to resonances preferentially decaying to one or more gluons, selection cuts are applied to tag jets as either quark-like or gluon-like, based on the number of tracks in the jet. The expected cross-section limits at 6 TeV are presented, and are shown to represent an improvement of up to 25% (for the significance of observing an excited quark using a single gluon tag). The results are consistent with the Standard Model.