According to the FMF, Carmona and Cruz Azul were informed on Wednesday of the ban in a ruling by the Court of Arbitration for Sport (CAS) in Switzerland. But he played against Pachuca in a league semifinal match Thursday.

Carmona tested positive for the banned steroid stanozolol in June 2005 and was banned for a year by the FMF. Despite another positive test by Carmona for the same substance on Jan. 31, 2006, the FMF disciplinary committee decided in July 2006 to nullify the results because it mistakenly believed the B sample was destroyed.

The World Anti-Doping Agency appealed to CAS for a life ban, which was upheld this week.

CAS rejected Carmona´s formal protest because it said the two-time World Cup player didn´t attempt to make any excuse which would have allowed CAS to consider a less severe sanction.

Carmona, who could not be reached for comment, apparently has filed a stay against the ban in federal court, arguing the FMF was interfering with his job.

"In the game yesterday between Cruz Azul and Pachuca, (Carmona) was in the lineup because of a legal challenge before a federal judge that we were not told about until 6:35 p.m., when the game already had started," FMF Secretary-General Decio de María said on Friday. "This is a very grave situation and at the moment the federation is analyzing the consequences."

He said Cruz Azul, which is still in the playoffs, might be disqualified for fielding an ineligible player. Cruz Azul officials did not return calls for comment.