  We study quark confinement by computing the Polyakov loop potential in
Yang--Mills theory within different non-perturbative functional continuum
approaches [1]. We extend previous studies in the formalism of the functional
renormalisation group and complement those with findings from Dyson--Schwinger
equations and two-particle-irreducible functionals. These methods are
formulated in terms of low order Green functions. This allows to identify a
criterion for confinement solely in terms of the low-momentum behaviour of
correlators.
