  We compute one-point function of the glueball loop operator in the maximally
confining phase of supersymmetric gauge theory using instanton calculus. In the
maximally confining phase the residual symmetry is the diagonal U(1) subgroup
and the localization formula implies that the chiral correlation functions are
the sum of the contributions from each fixed point labeled by the Young
diagram. The summation can be performed exactly by operator formalism of free
fermions, which also featured in the equivariant Gromov-Witten theory of P^1.
By taking the Laplace transformation of the glueball loop operator, we find an
exact agreement with the previous results for the generating function
(resolvent) of the glueball one-point functions.
