the garsia-procesi module $r_\lambda$ has a well known basis of artin monomials indexed by λ-subyamanouchi words, which correspond to the inv-statistic of the haglund-haiman-loehr combinatorial formula for the modified macdonald polynomials $h_\lambda(x;q,t)$ at $t=0$. we introduce a new basis for $r_\lambda$ of garsia-stanton descent monomials, giving a major-index type formula of the modified hall-littlewood polynomial $h_\lambda(x;q,t)$, and discuss the subtle connection to $h_\lambda(x;q,t)$ at $q=0$ via robinson-schensted-knuth insertion. our formula was discovered while searching for a basis of the garsia-haiman module by extending a similar result of carlsson and oblomkov for the diagonal coinvariants $dh_n$. this is joint work with e. carlsson.