  Quasi-particle spectra of the layer perovskite Sr$_2$RuO$_4$ are calculated
within Dynamical Mean Field Theory for increasing values of the on-site Coulomb
energy $U$. At small $U$ the planar geometry splits the $t_{2g}$ bands near
$E_F$ into a wide, two-dimensional $d_{xy}$ band and two narrow, nearly
one-dimensional $d_{xz,yz}$ bands. At larger $U$, however, the spectral
distribution of these states exhibit similar correlation features, suggesting a
common metal-insulator transition for all $t_{2g}$ bands at the same critical
$U$.
