Television cameras caught Gordon, who has since apologised for his comments, making an anti-gay slur to Portland Timbers midfielder Will Johnson during Sunday's game.
MLS Commissioner Don Garber said Gordon used "unacceptable and offensive language" and that he should attend diversity and sensitivity training.
"Major League Soccer stands against discrimination and prejudice of any kind and will not tolerate this type of behaviour," Garber said in a statement.
"All of our players, staff and fans must remain committed to respect and dignity at all times."
Gordon was also sent off in the 69th minute of Sunday's game after an elbow to the face of Timbers' French defender Mikael Silvestre and will serve an additional one game ban for that offence.
- Sports & Recreation