Alias: Baby Bull
Birthplace: Houston, Texas, USA
Hometown: Houston, Texas, USA
Height: 5′ 6″ / 168cm
Reach: 67″ / 170cm
Boxing Record: click
On November 22, 2003, Díaz won the WBC youth lightweight title with a sixth-round TKO of journeyman Joel Perez.
On July 17, 2004, Díaz defeated Mongolian Lakva Sim for the WBA lightweight title by unanimous decision. Since then, Díaz has defended the title five times. His most notable defense was on April 8, 2006 against undefeated Jose Miguel Cotto (brother of Miguel Angel Cotto). Díaz defeated Cotto by unanimous decision. On November 14, 2006, Diaz successfully defended his title for the fifth time against Fernando Angulo of Ecuador.
On April 28, 2007 he successfuly defended his title against Acelino Freitas by TKO after Freitas forfeited the fight before beginning the 9th round, unifying the WBO lightweight championship with the WBA lightweight title. The fight took place in Mashantucket, USA.
Diaz was 105-5 as an amateur. He thought he had qualified for the 2000 Mexican Olympic team but was informed he was too young to compete in Sydney. He didn't want to wait four more years and turned pro.
| WBA Lightweight Champion
17 July 2004 – present
| WBO Lightweight Champion
28 April 2007 – present