Quark mass anomalous dimension at O(1/Nf2) in QCD

We compute the d-dimensional critical exponents corresponding to the wave function and mass renormalization of the quark in QCD in the Landau gauge at a new order, O(1/Nf2), in the large Nf expansion. The computations are simplified by the establishment in d-dimensions of the critical point equivalence of QCD and the non-abelian Thirring model beyond leading order. The form of the O(1/Nf2) coefficients in the MS quark mass anomalous dimension at five loops is deduced and compared with the numerical asymptotic Padé approximant prediction.