Diego Simeone will not be able to coach Atletico Madrid for the remaining three matches of the Spanish league season as his team fights with Barcelona for the title.
The Spanish soccer federation on Wednesday rejected Atletico's appeal against the three-match ban.
The Argentine was sent off during last Saturday's1-0 win over Malaga after someone threw a second ball onto the field. The incident happened just as Malaga raced forward in a counter-attack and the second ball rolled onto the field close to the player running with the game ball, an action that the referee judged could have disrupted play.
After blowing the halftime whistle, referee Mateu Lahoz approached Atletico's bench and was heard telling Simeone "I have to send you off."
In its finding, the federation's competition committee said the club had failed to identify anyone and that "it has been established that the ball came from the area of Atletico's bench."
According to the game's regulations, the coach is held responsible if the perpetrator is not identified.
"The referee did the right thing," Simeone said after the match.
Simeone, who is well-known for his energizing pep talks and spirited encouragement, will be allowed to sit in his dugout for the Champions League match against Bayern Munich, but will have to sit in the stands for the rest of league season.
