The pulse duration of the near quarter-acoustic period (τa) is demonstrated in transient stimulated Brillouin scattering (SBS) pulse compression by the suppressing Stokes trailing-edge broadening at high intensities. A theoretical analysis reveals that the difficulty in attaining the transient compression limit is caused by the broadening of the Stokes trailing edge owing to insufficient pump depletion, and this undesirable phenomenon can be significantly suppressed by a high SBS gain coefficient. An average pulse duration of ∼1.05 τa was experimentally achieved in transient compression with a high-energy efficiency of over 30%. Benefiting from energy back conversion, compression below the transient SBS limit (< τa) also occurred when the pump peak power was increased to 150 MW.