Ichigo Kurosaki vs. Renji Abarai & Byakuya Kuchiki

Ichigo Kurosaki vs. Renji Abarai and Byakuya Kuchiki is a fight taking place in a street of Karakura Town. It is the final and most significant fight of the "Substitute Shinigami" arc. It is also the first fight between Ichigo Kurosaki and another Shinigami, foreshadowing many more still to come.

Prelude
When Rukia Kuchiki realizes Soul Society would soon be sending troops after her, she flees the Kurosaki Clinic, in an attempt to keep the heat off of Ichigo. When Ichigo learns of this he leaves immediately to try and stop her. Meanwhile Rukia is spotted by two Shinigami: Captain Byakuya Kuchiki, Rukia's adoptive older brother, and Lieutenant Renji Abarai of the 6th Division of Gotei 13. Uryū Ishida, who was following Rukia, intervenes to protect the unarmed Rukia, but is promptly dispatched by Renji.

Battle
Ichigo arrives at the scene just in time to stop Renji from landing a finishing blow on Uryū, catching him by surprise. Renji backs away to take a better look at the person who blocked him. Ichigo introduces himself, saying he will defeat Renji. Seeing a Shinigami before him, Renji is baffled for a second, but quickly recovers and connects the dots. Realizing Ichigo is the Human to whom Rukia gave her powers, Renji attacks. Ichigo soon finds himself on the defensive. Renji mocks Ichigo's abnormally large Zanpakutō and soon manages to slice deep into Ichigo's shoulder. Ichigo falls to his knees as Renji tells him that Rukia, after regaining her powers, will be taken to Soul Society and executed. Renji boasts that Ichigo could never even put a scratch on an experienced Shinigami like himself. This aggravates Ichigo, who responds with a sucker attack that scratches Renji's chin.

Byakuya intervenes for the first time, telling Renji he's been careless. Renji protests but Byakuya says Ichigo was responsible for the wounding of a Menos Grande two days before. Renji laughs in disbelief, disregarding the report, he asks Ichigo for the name of his Zanpakutō, which of course, Ichigo doesn't know. Renji then releases his Zanpakutō and reveals his Shikai, Zabimaru, explaining a Zanpakutō can change its shape and size in accordance with its wielder's spiritual power, telling ichigo he should return once he's trained for 2000 years. Renji attacks again, this time with a released Shikai. Ichigo attempts to block but is sliced badly through the shoulder by Zabimaru. Renji once again is about to administer a killing blow and once again is thwarted, this time by Rukia, who jumps on his back and cries for Ichigo to run away. Instead of running, Ichigo grabs the hilt of his sword and stands up to face Renji again.

Ichigo suddenly experiences an increase of his Reishi, noted also by the Shinigami surrounding him. His speed has also increased, though he doesn't not realize it himself. Before Renji has a chance to react, Ichigo slices through his shoulder, then turns around and attacks again, breaking Renji's sunglasses and leaving a gash in his forehead. Feeling his renewed Reishi like a surge of energy, Ichigo attacks the shocked Renji, intending to finish the fight. The attack fails to connect. Looking at his sword, Ichigo suddenly sees it only has about 6 inches of blade left. Realizing Renji couldn't have done it, Ichigo looks at Byakuya, who stands where he stood since the beginning of the fight, holding the rest of the blade in his hand. He then drops the blade and appears suddenly next to Ichigo while a huge amount of blood sprays out of Ichigo's chest.

Ichigo crumples to the ground. Rukia rushes to his side but is apprehended by Renji, he tells her she shouldn't aggravate her sentence by helping Ichigo any further, but she insists that she must as it is her fault that he is dying. Byakuya hears this and remarks that Ichigo bears a striking resemblance to him. Ichigo reaches and grabs Byakuya's uniform. Everyone is surprised to learn that Ichigo is still alive and conscious. Byakuya orders ichigo to let go, but Ichigo refuses. When Byakuya threatens to cut Ichigo's hand off Rukia rushes to kick Ichigo's hand away. She tells Ichigo to know his place and calls for her brother to leave in light of Ichigo's crude behavior.

Ichigo tries to get up but Renji stomps on his back and suggests he lays there and die quietly. Rukia tells Byakuya not to bother killing Ichigo, since he would probably die on his own. When Ichigo tries to stand up again she tells him to stay put, and that if he should try to follow her, she would never forgive him. Byakuya agrees to let Ichigo live, saying his attack, which cut through Ichigo's Saketsu and Hakusui, took away any trace of Shinigami power, even if he should survive. To Byakuya's order, Renji opens the Senkaimon and the three Shinigami depart to Soul Society.

Aftermath
Rukia is taken back to Soul Society, where she is sentenced to be executed by the Sōkyoku. Ichigo's life is saved by Kisuke Urahara, but he is forced to go through rigorous training in order to access his latent Shinigami powers, first awakened by Rukia's intervention. He also makes contact with his Zanpakutō. Uryū, Chad and Orihime also train with the intent to accompany Ichigo on his quest to save Rukia's life.

Renji and Byakuya return to their duties in the Gotei 13. Renji, revealed to be Rukia's life long friend, was convinced that her older brother would have her sentence commuted. He is shocked to learn the harsh sentence was imposed.