Ichigo Kurosaki vs. Grimmjow Jaegerjaquez

Ichigo Kurosaki vs. Grimmjow Jaegerjaquez is the first battle of the Arrancar Invasion of Karakura Town that involves a stated Espada fighting. This provided the difference between a common Arrancar and the most powerful of their kind, the Espada.

Prologue
After Rukia Kuchiki comes to Ichigo Kurosaki's aid and kills Grimmjow's Fraccion, Di Roy Rinker, they are both confronted by Grimmjow Jaegerjaquez; who introduces himself as the 6th Arrancar. Grimmjow approaches them, asking who is strongest. Rukia yells to Ichigo to get back, but before she can react Grimmjow impales her on his hand; noting that he thought she was not the more powerful. Enraged, Ichigo attacks Grimmjow.

Battle
As Ichigo strikes, Grimmjow effortlessly blocks the blade with his hand, and pushes Ichigo away. Grimmjow decides to toy with Ichigo, goading him to release his Bankai and attack him. After threatening to do to Ichigo what he did to Rukia, Ichigo releases his Bankai.

Once again Ichigo moves to attack but Grimmjow easily steps out of the way and grabs Ichigo's sword with his bare hand. Grimmjow then uses it as leverage to throw Ichigo a great distance. Grimmjow follows up but Ichigo appears behind him, much to the Espada's surprise. He counters Ichigo's attack, blocking it with his forearm and applying multiple kicks to Ichigo's head, sending him crashing into the buildings below. Grimmjow states he is unimpressed with Ichigo's Bankai, noting that it only enhances his speed. As the smoke clears Ichigo reveals that he has recovered and unleashes his Getsuga Tenshō. Grimmjow blocks it but it still lands a direct hit; greatly scarring his torso. Rather than being enraged Grimmjow is surprised and delighted at the technique.

Grimmjow laughs, noting that this turn of events is great seeing as now he finds Ichigo worth killing. Grimmjow takes out his Zanpakuto and states that Ichigo shouldn't just stand there as now its his turn. Before Grimmjow can act he is stopped by the arrival of Kaname Tōsen, who orders him to sheath his sword. Grimmjow becomes enraged that Tōsen is there. Tōsen explains that he has attacked the Human World, mobilizing five Arrancar without permission and leading them to their deaths. Tōsen further states that the fact that it was all against orders has made Aizen furious and tells him that his punishment will be decided in Hueco Mundo. Tōsen opens a Garganta and the two leave, despite Grimmjow being unwilling to go. When Ichigo demands him to come back as their fight isn't over yet, Grimmjow states that he is a fool, as the only reason he still lives is because the fight isn't over. He then notes how Ichigo's Getsuga Tenshō is damaging his own body and that its use is limited. Even if he could continuously use the technique its still not powerful enough to defeat his released state. His parting words are for Ichigo to remember his name, and pray that he never hears it again for if he does it will be that last thing he hears.

Aftermath
The results of the fight became a severe reality check as well as morale breaker for Ichigo. When Renji Abarai states that he won, Ichigo claims that he lost. He realizes the threat that the Arrancar possess and the power level necessary to defeat them. A power level that he doesn't currently possess. With the realization that he has to get stronger in order to protect his friends and his home he is gonna have to take drastic measures. He decides to go and ask for help from the Visored.

When Aizen refuses to punish Grimmjow, Tōsen grabs him and asks that he be allowed to execute him. Grimmjow notes that he must have a personal problem with him, which causes Tōsen to explain that he serves justice and doesn't tolerate those who sow discord. He then suddenly severs and incinerates Grimmjow's left arm. Enraged Grimmjow moves to attack him but is quickly told to stop by Aizen, who reminds him that if he were to attack Tōsen he would have no reason to pardon him. Realizing his situation Grimmjow reluctantly leaves. This act of losing his arm results in Grimmjow's loss of his position as the 6th Espada.