We consider an extended Nambu-Jona-Lasinio model for the light-meson sector
of QCD, where unphysical quark-production thresholds are excluded by an in
frared cutoff on the momentum integration within quark-loop diagrams. This
chiral quark model conserves low-energy theorems. The infrared cutoff is fi
xed by the dynamically generated quark mass (quark condensate). The sigma-m
eson mass and decay width are estimated within the model.