The spectral correlations of the QCD Dirac operator in the 4-dimensional Euclidean box, 1/ΛQCD ≪ L ≪ 1/mπ, usually denoted as Leutwyler-Smilga regime [3], have been the object of intense study in recent years. They contain valuable information about the chiral properties of the QCD vacuum. Provided that chiral symmetry is spontaneously broken, the above regime can be described either by an effe...