The computation of the single-differential top quark-antiquark pair (t t ¯) production cross section at NLO in the fixed-order expansion is examined consistently using the MSR and MS¯ short-distance top quark mass schemes. A thorough investigation of the dependence of different regions of the t t ¯ invariant mass spectrum on the renormalization scales R and μm of the MSR mass mtMSR (R) and MS¯ mass m¯ t(μm), respectively, is carried out. We demonstrate that a scale choice of R ~ 80 GeV is important for the stability of the cross-section predictions for the low t t ¯ invariant mass range, which is important for a reliable extraction of the top quark mass. Furthermore, a choice of semi-dynamical renormalization and factorization scales is preferred. These findings are expected to remain valid once non-relativistic quasi-bound state effects are included in the low invariant mass region.