Tsunayoshi Sawada vs. Hayato Gokudera is a battle fought between Tsunayoshi Sawada and Hayato Gokudera, which took place in Namimori Middle School. It is the first battle shown in the series, though not the first chronologically.
A new transfer student from Italy, Hayato Gokudera, is introduced to Tsuna’s class. As Tsuna's female classmates express their interest, Gokudera goes over to Tsuna’s desk and kicks it. After class, Tsuna is thinking about Gokudera’s actions, thinking that he can’t get along with him. He accidentally bumps three seniors and runs for it before he gets beaten.
Tsuna meets up again with Gokudera who reveals his awareness of the Vongola Famiglia and the Mafia and tells Tsuna that he deserves to be the 10th boss, not Tsuna. Tsuna is confused and is surprised to see Gokudera light some dynamite and throw it at him. However, Reborn arrives and stops the dynamite from exploding. Reborn and Gokudera then introduce themselves to each other. Reborn tells Gokudera that if he killed Tsuna, he could be a candidate to be the 10th boss.
Tsuna, thinking that Reborn betrayed him, tries to run for it, but Gokudera easily catches up to him and lights up more dynamite. Tsuna is able to dodge the dynamite until he ends up cornered. Reborn shoots Tsuna with one of his Dying Will Bullets, making Tsuna go into Dying Will Mode and defuse all of the dynamite. Gokudera tries to throw Double Bombs, but Tsuna defuses all of those ones as well. Angered, Gokudera tries to use Triple Bombs, but he accidentally drops them. Gokudera, thinking that he was going to die, is surprised to see Tsuna defuse the rest of the dynamite around him, saving his life.
Gokudera immediately apologizes, saying that he will follow Tsuna’s commands, and forces Tsuna to make him his right-hand man. Tsuna is too scared to refuse.