  Two of the most interesting experimental results of heavy-ion reactions at
RHIC collider energies are in the hard scattering sector where central Au+Au
data show a very different behaviour compared to p+p and peripheral Au+Au
collisions. The so-called ``high p_T pi^0 suppression'' and the ``anomalous''
baryon/meson ratio observed by PHENIX in central Au+Au collisions at
sqrt(s_{NN}) = 200 GeV are reviewed and compared to various theoretical
calculations based on different strongly interacting medium scenarios.
