One Piece Chapter 51, page 16-17: Roronoa Zoro Falls Into the Sea

The chefs on the Baratie watch in awe, shouting, "He unsheathed it! That sword he used to cut our ship with!" Zoro prepares for the final clash, spinning his swords rapidly, thinking, "So this is it... the final blow... If I miss here, I'll die... To be the world's strongest... or to die here and now...!" Mihawk charges, shouting, "Die!" Luffy screams in panic, "Bro, that's enough! Stop!" Zoro prepares his ultimate technique: "SANTOURYUU OUGI!" (Three swords style secret).

Zoro unleashes his ultimate attack, shouting, "SANZEN SEKAI!!" (3000 Worlds). The two swordsmen clash in a flash of light. As they pass each other, Zoro's two ordinary swords shatter into pieces. Zoro stands silently, realizing his defeat, thinking, "I lost... I'm no match for him... Never even thought about the possibility of losing... So this is... the strength of the world's strongest...!" With a quiet click, he sheathes his remaining sword, Wado Ichimonji.