Laser-driven hypervelocity impact experiments were used to study pressure-induced long-term effects on the crystal structure of undoped GaSb. X-ray diffraction and confocal micro-Raman spectra were collected on unshocked and shock-compressed samples, with corresponding pressures ranging between 8 and 23 GPa. GaSb retained bulk crystallinity at 8 GPa but showed localized site disordering, transformed into an amorphous state at 13 GPa, and stayed in that phase until 23 GPa.