  We show, within the framework of renormalized nuclear field theory and of the
induced reaction surrogate formalism, that the highly debated $^{10}$Li
structure, observed in a recent $^9$Li(d,p)$^{10}$Li one--neutron transfer
experiment is consistent with or better, requires the presence of a virtual
$1/2^+$ state of similar single--particle strength than that of the $1/2^-$
resonance at 0.45$\pm$ 0.03 MeV. Based on continuum spectroscopy self-energy
techniques, we find that the physical mechanism responsible for parity
inversion in $^{10}_3$Li is the same as that at the basis of the similar
phenomenon observed in $^{11}_4$Be and to that needed in $^{11}$Li to have an
important $s$--wave ground state component. Furthermore, it is also consistent
with the (normal) sequence of the $1p_{1/2}$ and $2s_{1/2}$ levels in the $N=7$
isotones $^{12}_5$B and $^{13}_6$C.
