The electrical resistivity of the magnetically ordered CeCu5Au has been inv
estigated under pressure up to 8.5 GPa. In the magnetically ordered region
(p < 3.4GPa) the residual resistivity rho (0) shows a pronounced maximum as
a function of pressure. Even in the non-magnetic region rho (0) decreases
monotonically by more than a factor of three. These two effects can be qual
itatively explained in terms of the interplay of pressure, magnetism and di
sorder in a strongly correlated electron system with weak disorder.