  The behavior of the mesons and diquarks is studied at finite temperatures,
chemical potentials and densities, notably when the color superconductivity is
taken into account. The Nambu and Jona-Lasinio model complemented by a Polyakov
loop (PNJL description) has been adapted in order to model these composite
particles in this regime. This paper focuses on the scalar and pseudo-scalar
mesons and diquarks, in a three-flavor and three-color description, with the
isospin symmetry and at null strangeness. A finality of this work is to
underline the modifications carried out by the color superconducting regime on
the used equations and on the obtained results. It has been observed that the
two-flavor color-superconducting (2SC) phase affects the masses of the mesons
and diquarks in a non-negligible way. This observation is particularly true at
high densities and low temperatures for the pions, $\eta$ and the diquarks [ud]
whose color is rg. This reveals that the inclusion of the color
superconductivity is relevant to describe the mesons and diquarks near the
first order chiral phase transition.
