Phoenix Rising midfielder Junior Flemmings received a six-game suspension from USL Championship for homophobic abuse during a match against the San Diego Loyal.
The slur was directed at Loyal midfielder Collin Martin, who is gay. San Diego players walked off the field and forfeited the 30 September match in protest.
Flemmings is currently on leave and could face further discipline by the Rising. The league suspension includes all the league's playoff games.
The USL Championship's action comes after an investigation that included interviews with 11 people, including players and match officials.
The Loyal, coached by former US national team star Landon Donovan, was leading 3-1 when the players decided to leave the field in support of Martin.
The incident came a week after the Loyal asked to forfeit their 1-1 tie at the Los Angeles Galaxy II because San Diego's Elijah Martin was called a racial slur.
The USL Championship is the second tier of US soccer, below Major League Soccer.
AP
