Let S w (x) = S w (x 1 , . . . , x n ) be the Schubert polynomial for a permutation w of {1, 2, . . . , n}. For a composition µ = (µ 1 , . . . , µ n ) ∈ Z n ≥0 , writewith respect to µ. Huh, Matherne, Mészáros and St. Dizier proved that N() is a Lorentzian polynomial, where N is a linear operator sending a monomialThey further conjectured that N(S w (x)) is Lorentzian. Motivated by this conjecture, we investigate the problem when x µ S w (x −1 ) is still a Schubert polynomial. If x µ S w (x −1 ) is a Schubert polynomial, then N(S w (x)) will be Lorentzian. In this paper, we pay attention to the typical case that µ = δ n = (n − 1, . . . , 1, 0) is the staircase partition. Our result shows that x δn S w (x −1 ) is a Schubert polynomial if and only if w avoids the two patterns 132 and 312.