Chávez won his first championship, the vacant WBC super featherweight title, on September 13, 1984, by knocking out fellow Mexican Mario "Azabache" Martínez at the Grand Olympic Auditorium in Los Angeles, California. Martínez had been the betting favorite in the bout.
On July 7, 1985, Chavez defeated future champion Roger Mayweather via a second round knock out. On August 3,1986, Chavez defeated former WBA and future IBF Super Featherweight champion Rocky Lockridge. In his next bout, he defeated former champion Juan Laporte. He successfully defended his WBC Super Featherweight title a total of ten times.
On December 21, 1987, Chávez moved up to the lightweight division and brutally defeated Edwin Rosario (Puerto Rican). Angered by how Rosario had insulted the Mexican people before the match, Chávez gave him a vicious beating and won the title with an 11th round technical knockout (TKO) to win the WBA lightweight championship. In 1988, he successfully defended his title against former two-time champion Rafael Limon. Later that year, he unified the WBA and WBC belts by a technical decision win over José Luis Ramírez. An accidental head-butt opened a cut on Ramírez's forehead and the doctor halted the fight, sending the decision to the judges' scorecards at that point in the fight. Chávez, ahead on all scorecards, was declared the winner.
Chavez vacated his WBA and WBC lightweight titles in order to move up to the super lightweight division. In his next bout, he won the WBC super lightweight title by knocking out Roger Mayweather for a second time. In 1989, Chávez defeated future champion Sammy Fuentes and a month later, he handed Alberto de las Mercedes Cortes (44-0) his first career loss.
In March 17, 1990, he faced Meldrick Taylor (see Chavez versus Taylor), the IBF Junior Welterweight champion, in a title unification fight. While Taylor won the early rounds, Chávez rallied in the later rounds, scoring a knockdown with 16 seconds remaining in the final round. Although Taylor rose at the referee's count of six, he did not respond coherently to referee Richard Steele's questions, continued to hold the ropes all along, and Steele stopped the fight with only two seconds remaining. Many boxing fans and members of the media were outraged that Steele would stop a match that Taylor was winning with only two seconds left, while others felt that Steele was justified in stopping the fight given Taylor's condition and the fact that he was unable to respond to Steele before the conclusion of the match. Steele defended his decision by saying that his concern is protecting a fighter, regardless of how much time is left in the round or the fight. As Steele put it, "I stopped it because Meldrick had took a lot of good shots, a lot of hard shots, and it was time for it to stop. You know, I'm not the timekeeper, and I don't care about the time. When I see a man that has had enough, I'm stopping the fight. Ring Magazine named it the "Fight of the Year" for 1990, and later the "Fight of the Decade" for the 1990s. While many hoped for an immediate rematch, Taylor moved up in weight in his next bout and the fighters did not meet again until 1994 when Chávez dominated and then knocked out Taylor, whose skills had significantly diminished in the ensuing years.
After unifying the titles, Chávez engaged in a busy series of title defenses and non-title fights, which included wins over former champion Lonnie Smith and rival Hector Camacho. His 1993 fight with Greg Haugen featured trash talk from Haugen, who derided Chavez's 82-fight unbeaten streak as consisting mostly of "Tijuana taxi drivers that my mother could have knocked out" and insisting that "There aren't 130,000 Mexicans who can afford tickets" to see the fight in Estadio Azteca. Haugen was proven wrong on both counts: 136,274 showed up to set a record for fight attendance, and they watched Chávez drop Haugen quickly and then back off with the apparent intention of punishing him for his prefight remarks. However, the referee had seen enough by the fifth round and stopped it for a TKO victory for Chávez. After the fight, Chávez asked Haugen about his comment about the Tijuana taxi drivers, and Haugen sportingly responded, "They must have been tough taxi drivers."
After eleven successful title defenses, Chávez moved up one more weight division to challenge Pernell Whitaker for his WBC welterweight title in September 1993.Chavez being the stalker and whittiker being the runner. Chavez would punish whittiker every time they would actualy stand and fight, but whittiker preffered to punch and run. The fight endid in a draw, which to some did not seem fair, since whittiker was running away all night long. The draw became the first blemish on Chávez's record, as he had won all his previous fights. A rematch did not come to pass.
Chávez faced Frankie Randall in January 1994, in a fight that most expected him to win easily. Instead, Randall knocked him down for the first time in his career and went on to win a split decision. Chávez blamed his loss on referee Richard Steele, who deducted two points from Chávez for low blows, which ultimately made the difference on the scorecards. After the fight it was discovered that both frankie randels ribs were broken and speculation arose that he was on steroids.
The WBC ordered an immediate rematch and Chávez regained the title on a split technical decision in May, 1994. The fight was fiercely contested when a clash of heads opened a large cut over Chávez's brow in the seventh round. Chavez came back strong and showed he was the better boxer, after the head cut, the referee called for the doctor who then instructed for the fight to be stopped. Under WBC rules, Randall was deducted one point, and that gave Chávez the technical victory on the score cards. The two would face one another in a rubber match ten years later in which the great julio cesar chavez would easily win.
In 1994, Chavez then faced Meldrick Taylor in a rematch, 4 years after their historic first fight. Taylor was determined to get revenge on Chavez,and to his surprise Julio Cesar Chavez had become far greater than taylor expected. Chavez defeated him via an 8th round knockout, that sent Taylor from one side of the ring to the other. In his next bout, Chavez defeated former three-time champion Tony Lopez. In 1995, he defeated former lightweight and future super lightweight champion Giovanni Parisi.
Chávez continued to defend his WBC super lightweight title against unheralded opposition until he faced Oscar de la Hoya in 1996. A large gash appeared over the right eye of Chávez within the first minute of the first round, leading many to assume what Chávez later confirmed--that the cut occurred earlier in training and was reopened in the bout. Heavy blood flow prompted the referee to stop the fight in the fourth round. Until their eventual rematch in 1998, Chavez would always state that de la Hoya had not defeated him, but that a gash that he had suffered in training was the real cause of the stoppage of the fight. In his next bout, Chavez defeated former champion Joey Camache.
A year after de la Hoya moved up to welterweight in 1997, Chávez fought Miguel Angel Gonzalez for the vacant WBC super lightweight title. That fight ended in a draw. He challenged for a title on two other occasions, coming up short in both.
In a rematch with de la Hoya for the WBC welterweight belt in September 1998, de la Hoya decided not to use his speed and reach advantages, and instead chose to punish Chávez repeatedly to the head and the body in an effort to force a stoppage that could not be disputed. After the eighth round, video shows Chávez telling his corner he couldn't continue because of severe laceration on his lip and the fight was stopped.
After a 2001 victory over Terry Thomas in Ciudad Juarez, Mexico, Chávez retired. However, on November 24, 2003, he came out of retirement to avenge his earlier loss to Willy Wise, knocking Wise out in two rounds in Tijuana, Mexico.
In April 2004, Chávez went back into the ring, for what he again claimed would be his last appearance. In that fight, nicknamed Adiós, México, Gracias (Good-bye, Mexico, Thank you), he beat his former conqueror, Frankie Randall, by a ten round decision.
On May 28, 2005, Chávez once again stepped into a boxing ring, outpointing Ivan Robinson in ten rounds at the Staples Center. On September 17, 2005, at the U.S. Airways Center in Phoenix, Arizona, Chávez suffered a TKO loss to little-known Grover Wiley, retiring in his corner before the start of the 5th round, apparently due to an injury to his right hand. After the bout, Chávez told his promoter, Bob Arum, that this time he was definitely retiring from boxing.
Chávez finally retired with a record of 108 wins, 6 losses and 2 draws, with 87 knockouts, and was one of the best boxers of all time. He holds records for most successful defenses of world titles (27) and most title fights (37). ESPN recently ranked him as the 24th greatest boxer in history. His son, Julio Jr., is also a professional boxer.
In 2002, Ring Magazine ranked Chávez as the 18th greatest fighter of the last 80 years. He was also ranked #50 on Ring Magazine's list of 100 greatest punchers of all time.
He had a boxing videogame with his brand for the Super Nintendo.
After being threatened by a gang that his son would be kidnapped, Chávez became one of the first people to denounce the kidnappings of famous people's relatives in Mexico during the middle and late 1990s.
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