Miguel Diaz (Xolo Maridueña) is an Ecuadorian American teenage asthmatic with low self-esteem and is Johnny's neighbor. While shopping for Pepto-Bismol for his grandmother at a strip mall in Reseda, he is attacked 의해 a group of rich bullies led 의해 Kyler after accidentally foiling their plans to buy beer. The bullies nickname him "Rhea" after noticing the bottle of Pepto-Bismol and dump it all over him. When the bullies shove him onto Johnny's car, Johnny attacks them, beating them senseless before he is arrested. Miguel becomes Johnny's first student in the new 코브라 Kai dojo. Aside from learning karate, he is the dojo's housekeeper and website administrator. Though initially reluctant and mocking towards him, Johnny quickly comes to care for Miguel, becoming a father figure to him, despite objections from his mother.
When Daniel's daughter Sam confronts Kyler over vicious rumors he spread about her after she fought off his attempt to 날짜 rape her, Miguel beats up Kyler and his clique, gaining popularity in the school and earning Johnny's gi as the fight leads to an influx of new members to 코브라 Kai. Despite Johnny's warning that he should avoid the LaRussos, Miguel begins dating Sam. Unfortunately, they break up after four months of dating when Miguel wrongly suspects Sam of cheating on him with Johnny's son, Robby, leading to an altercation in which Miguel accidentally punches Sam. 코브라 Kai's thuggish philosophy begins to affect Miguel's values and he becomes much 더 많이 violent and ruthless, to Johnny's eventual disapproval, especially when Miguel fights dirty against Robby in the All-Valley.
In Season 2, friction develops between Johnny and Miguel when Miguel finds out the truth about Robby's parentage. Johnny makes amends with his 별, 스타 pupil 의해 telling him the story of Robby's birth and how he was never there for him to his regret. He promises to do better 의해 Miguel than he did with Robby. Miguel is also wary of Kreese, noticing inconsistencies in Kreese's stories about his supposed military exploits during the '80s and '90s. He vehemently disapproves of Kreese's style of teaching, and when he finds out that Hawk's gang trashed Miyagi-Do and 스톨, 훔친 Mr. Miyagi's Medal of Honor, he defeats Hawk in a brutal fight during a competition at Coyote Creek and returns the medal to Robby at Daniel's home, but not before appalling Johnny with his ruthlessness (which Johnny realizes is a result of Kreese's teaching).
Miguel develops a relationship with new 코브라 Kai student Tory Nichols, but he still has feelings for Sam, culminating in him 키싱 her at a party after she learns from Aisha the truth about the medal (which Robby had withheld from her). The act is seen 의해 Tory, who challenges Sam to a fight in school the 다음 morning. In the ensuing rumble, Miguel once again battles Robby and even taunts Robby 의해 mocking his relationship problems with Johnny and Sam. After a lengthy fight, Miguel gets Robby in an arm lock and nearly decides to break his arm, but chooses to show him mercy after remembering a conversation where Johnny expressed regrets over not learning to show mercy at a younger age. However, Robby, furious at Miguel for having a better relationship with his father Johnny than he ever did and seemingly taking advantage of Sam, furiously retaliates 의해 kicking Miguel over the balcony railing and accidentally sends him falling off the 초 floor. Miguel hits his back on the stair railing as he lands, paralyzing him and leaving him in a coma.
In Season 3, when Miguel wakes up from his coma, he is initially resentful to Johnny for his predicament about showing mercy, but slowly reconciles with him when the latter becomes personally involved in his physical rehabilitation. Several people pitch in to pay for Miguel's surgery, Johnny 의해 stealing and pawning a modern art sculpture from his stepfather, Bobby using proceeds from his church, and Sam 의해 organizing a car wash fundraiser, although the 코브라 Kais decide to initiate conflict with the Miyagi-Dos 의해 stealing the proceeds to donate in their own name.
Under Johnny's mentorship, Miguel is able to gain full function of his legs. As Johnny has been kicked out of 코브라 Kai 의해 Kreese in the wake of the school brawl, he and Miguel open a new martial arts dojo, Eagle Fang, with students Kreese had ejected from 코브라 Kai. He also cuts his ties with his 코브라 Kai 프렌즈 after finding out how Hawk broke Demetri's arm during the laser tag fight, and also learns that Kyler has joined 코브라 Kai. This act wins over Sam, who resumes her romance with Miguel and gets her father to connect with him when he catches them making out in the Miyagi dojo. Daniel is surprised to find common ground with Miguel over their shared upbringings (coming from a poor, single-parent family, being bullied 의해 wealthier kids, and finding guidance through karate) and agrees to let them continue dating. Miguel also works with Sam to save the All Valley tournament, and aids her in creating an alliance between Eagle Fang and Miyagi-Do, helping them fight off the 코브라 Kais when Tory leads them in an assault on the LaRusso residence. In the fight, Miguel is singled out for a one-on-one fight with Kyler, who seeks payback for the lunchroom fight. Kyler brutally beats Miguel, but Miguel gains a 초 wind when he remembers all of Johnny's encouragement, and quickly defeats Kyler with a takedown counterattack.
Miguel returns to his mother's apartment to tend to his wounds from the fight, which is how Johnny finds him when he shows up at the Diaz apartment seeking to declare his 사랑 to Carmen. An enraged Johnny immediately sets out to 코브라 Kai to confront Kreese, as does Daniel. Miguel and Sam manage to chase them down, showing up at 코브라 Kai just as Daniel is about to finish off Kreese, bringing him and Johnny to their senses.
During the aftermath, Johnny and Miguel bring their fellow students to the Miyagi dojo to help train both dojo's students.
When Daniel's daughter Sam confronts Kyler over vicious rumors he spread about her after she fought off his attempt to 날짜 rape her, Miguel beats up Kyler and his clique, gaining popularity in the school and earning Johnny's gi as the fight leads to an influx of new members to 코브라 Kai. Despite Johnny's warning that he should avoid the LaRussos, Miguel begins dating Sam. Unfortunately, they break up after four months of dating when Miguel wrongly suspects Sam of cheating on him with Johnny's son, Robby, leading to an altercation in which Miguel accidentally punches Sam. 코브라 Kai's thuggish philosophy begins to affect Miguel's values and he becomes much 더 많이 violent and ruthless, to Johnny's eventual disapproval, especially when Miguel fights dirty against Robby in the All-Valley.
In Season 2, friction develops between Johnny and Miguel when Miguel finds out the truth about Robby's parentage. Johnny makes amends with his 별, 스타 pupil 의해 telling him the story of Robby's birth and how he was never there for him to his regret. He promises to do better 의해 Miguel than he did with Robby. Miguel is also wary of Kreese, noticing inconsistencies in Kreese's stories about his supposed military exploits during the '80s and '90s. He vehemently disapproves of Kreese's style of teaching, and when he finds out that Hawk's gang trashed Miyagi-Do and 스톨, 훔친 Mr. Miyagi's Medal of Honor, he defeats Hawk in a brutal fight during a competition at Coyote Creek and returns the medal to Robby at Daniel's home, but not before appalling Johnny with his ruthlessness (which Johnny realizes is a result of Kreese's teaching).
Miguel develops a relationship with new 코브라 Kai student Tory Nichols, but he still has feelings for Sam, culminating in him 키싱 her at a party after she learns from Aisha the truth about the medal (which Robby had withheld from her). The act is seen 의해 Tory, who challenges Sam to a fight in school the 다음 morning. In the ensuing rumble, Miguel once again battles Robby and even taunts Robby 의해 mocking his relationship problems with Johnny and Sam. After a lengthy fight, Miguel gets Robby in an arm lock and nearly decides to break his arm, but chooses to show him mercy after remembering a conversation where Johnny expressed regrets over not learning to show mercy at a younger age. However, Robby, furious at Miguel for having a better relationship with his father Johnny than he ever did and seemingly taking advantage of Sam, furiously retaliates 의해 kicking Miguel over the balcony railing and accidentally sends him falling off the 초 floor. Miguel hits his back on the stair railing as he lands, paralyzing him and leaving him in a coma.
In Season 3, when Miguel wakes up from his coma, he is initially resentful to Johnny for his predicament about showing mercy, but slowly reconciles with him when the latter becomes personally involved in his physical rehabilitation. Several people pitch in to pay for Miguel's surgery, Johnny 의해 stealing and pawning a modern art sculpture from his stepfather, Bobby using proceeds from his church, and Sam 의해 organizing a car wash fundraiser, although the 코브라 Kais decide to initiate conflict with the Miyagi-Dos 의해 stealing the proceeds to donate in their own name.
Under Johnny's mentorship, Miguel is able to gain full function of his legs. As Johnny has been kicked out of 코브라 Kai 의해 Kreese in the wake of the school brawl, he and Miguel open a new martial arts dojo, Eagle Fang, with students Kreese had ejected from 코브라 Kai. He also cuts his ties with his 코브라 Kai 프렌즈 after finding out how Hawk broke Demetri's arm during the laser tag fight, and also learns that Kyler has joined 코브라 Kai. This act wins over Sam, who resumes her romance with Miguel and gets her father to connect with him when he catches them making out in the Miyagi dojo. Daniel is surprised to find common ground with Miguel over their shared upbringings (coming from a poor, single-parent family, being bullied 의해 wealthier kids, and finding guidance through karate) and agrees to let them continue dating. Miguel also works with Sam to save the All Valley tournament, and aids her in creating an alliance between Eagle Fang and Miyagi-Do, helping them fight off the 코브라 Kais when Tory leads them in an assault on the LaRusso residence. In the fight, Miguel is singled out for a one-on-one fight with Kyler, who seeks payback for the lunchroom fight. Kyler brutally beats Miguel, but Miguel gains a 초 wind when he remembers all of Johnny's encouragement, and quickly defeats Kyler with a takedown counterattack.
Miguel returns to his mother's apartment to tend to his wounds from the fight, which is how Johnny finds him when he shows up at the Diaz apartment seeking to declare his 사랑 to Carmen. An enraged Johnny immediately sets out to 코브라 Kai to confront Kreese, as does Daniel. Miguel and Sam manage to chase them down, showing up at 코브라 Kai just as Daniel is about to finish off Kreese, bringing him and Johnny to their senses.
During the aftermath, Johnny and Miguel bring their fellow students to the Miyagi dojo to help train both dojo's students.