Díaz attended Roberto Clemente High School in Chicago where he was honored as an Illinois All-State baseball player each of his four years there. As a high schooler, he was invited to dinner by fellow Dominican and star Chicago Cubs outfielder Sammy Sosa. He attended Grayson County College where he was a first-team National Junior College Athletic Association All-American. He was selected by the Los Angeles Dodgers in the 37th round of the 2000 Major League Baseball draft and signed as an infielder. Díaz achieved quick success as a minor league hitter, winning the Gulf Coast League batting title in with a.354 batting average. He managed the same feat the following year hitting.350 in the South Atlantic League. In, he was traded by the Dodgers to the New York Mets for Jeromy Burnitz. Because of his limited fielding skills, the Mets moved Diaz to the outfield in. Díaz made his major league debut with the Mets on September 11, 2004. He was impressive during his September tryout, hitting a three-run home run with two outs in the bottom of the ninth inning to win a pivotal game against the playoff-contending Chicago Cubs, essentially knocking them out of the playoffs on September 25, 2004. After the 2004 season, the Mets included Dìaz on their 2005 Opening Day roster, and he wound up playing his first full Major League season, as in 89 games he hit.257 with 12 home runs and 38 R.B.I.s. On August 22, 2006, Diaz was designated for assignment by the Mets. On August 30, 2006, Diaz was dealt to the Texas Rangers for Mike Nickeas. After the 2006 season, Diaz headed to the Instructional League to work with hitting coachBrook Jacoby on his swing, then he played in the Dominican Winter League. Diaz competed for a spot on the Rangers 25-man roster, but did not make the cut and started the season with Triple-A Oklahoma. Diaz was called up and absolutely wowed Rangers fans, as he hit 9 home runs in only 104 at-bats and only 25 hits. He only appeared in 37 games for the Rangers in, but even with his performance, became a free agent after the season. On January 11, 2008, Diaz signed a minor league contract with the Houston Astros, but was released on May 2, 2008. Shortly thereafter, he signed a minor league contract with the Seattle Mariners and was assigned to their Triple-A affiliate, the Tacoma Rainiers. He became a free agent at the end of the season. On December 1, 2008, he signed with the Hanwha Eagles in South Korea. But he was released from Hanwha on July 8, 2009. On July 19, 2009, Díaz signed a minor league deal with the Baltimore Orioles and was assigned to their minor league affiliate, the Norfolk Tides. WFAN personality Joe Benigno is occasionally ridiculed for projecting Díaz to have a better offensive career than then-teammates José Reyes and David Wright in 2005. Over his career, Dìaz was known for swinging at the ball aggressively, as he only walked 32 times in 1 full season and parts of 3 seasons. Growing up, the Chicago Cubs were his favorite baseball team, and Sammy Sosa was his favorite player. It has been said that Dìaz always wanted to do everything in baseball the way Sosa would. In 2012, Díaz signed a one-year deal worth $200,000 dollars and a $50,000 signing bonus to play professionally in Japan for the Chunichi Dragons In 2013, Diaz played for the Bridgeport Bluefish of the Atlantic League of Professional Baseball, and batted.172 with 2 homeruns and 46 strikeouts. In the summer of 2014, Diaz played in the Westchester-Rockland Wood Bat League and hit.340 during the regular season while playing in only 17 games, and .500 with two homeruns in 6 postseason games Diaz signed with the Grand Prairie AirHogs of the American Association of Independent Professional Baseball for the 2015 season.
