  The seniority scheme has been shown to be extremely useful for the
classification of nuclear states in semi-magic nuclei. The neutron-proton
($np$) correlation breaks the seniority symmetry in a major way. As a result,
the corresponding wave function is a mixture of many components with different
seniority quantum numbers. In this contribution we show that the $np$
interaction may favor a new kind of coupling in $N=Z$ nuclei, i.e., the
so-called isoscalar spin-aligned $np$ pair mode. Shell model calculations
reveal that the ground and low-lying yrast states of the $N = Z$ nuclei
$^{92}$Pd and $^{96}$Cd may mainly be built upon such spin-aligned $np$ pairs
each carrying the maximum angular momentum $J = 9$ allowed by the shell
$0g_{9/2}$ which is dominant in this nuclear region.
