  A model is introduced with a massive scalar coupling to the Yang--Mills term
in four--dimensional gauge theory. It is shown that the resulting potential of
colour sources consists of a short range Coulomb interaction and a long range
confining part. Far away from the source the scalar vanishes $\sim r^{-1}$
while the potential diverges linearly $\sim r$. Up to an $N_c$--dependent
factor of order 1 the tension parameter in the model is $gmf$, where $m$
denotes the mass of the scalar and $f$ is a coupling scale entering the
scalar--gluon coupling.
