Jose Canseco denies doping claim

Mexican Baseball League officials say Jose Canseco has acknowledged that he took a banned substance for which he has no prescription and will not play in the league.

Plinio Escalante, president of the Mexican League, confirmed to ESPN Deportes that the banned substance is testosterone.

A source told ESPN Deportes that Canseco refused to take a doping test.

Canseco took to Twitter Wednesday to refute the allegations.

"How can I test positive when I never took any test don't believe everything the media tells you.the truth always comes out I am not using any illegal substanced," Canseco tweeted. "Don't be so quick to judge till you here the truth that's a sure sign of ignorance hatred and jealousy."

Canseco, a former MLB All-Star, tried out for the Quintana Roo Tigers of the Mexican League, according to a team announcement Feb. 12. Canseco, 47, last played in the majors for the Chicago White Sox in 2001.

"Back in baseball I knew I would play this year you just gotta believe in your dreams," Canseco wrote on Twitter Feb. 12. "Leave on redeye tonite to start spring training with AAA quintana roo tigers tomorrow . TEam won league championship last year."

The Mexican league is part of the MLB's minor league system at the Triple-A level, but its teams are not affiliated with individual major league clubs.

Canseco, the 1988 AL MVP, played for seven teams in his 17-year career and hit 462 homer runs. In 2005, he admitted to using anabolic steroids and later published a book in which he said 85 percent of major league players used banned substances.