In a statement released on Tuesday, the league said: "The USL Championship announced on Tuesday, following an investigation that included interviews with 11 individuals, including players, coaches and match officials, that it has issued a six-game suspension and undisclosed fine to Phoenix Rising FC's Junior Flemmings for the use of foul and abusive language in the form of a homophobic slur during the club's match against San Diego Loyal SC on September 30.
"Per the player's contract, Flemmings could also be subject to additional discipline from Phoenix Rising FC and remains on administrative leave.
"Flemmings' suspension covers the entirety of the 2020 USL Championship Playoffs."
At the end of the first half in last Wednesday's match, the Loyal's Martin received a red card while talking with the referee. During the discussion, Martin maintained that Flemmings called him a slur late in the half. In June 2018, Martin came out as gay while with MLS' Minnesota United.
Martin's red card was subsequently rescinded by the referee, who initially thought Martin was using the slur toward him.
The San Diego club is co-owned and coached by Landon Donovan, the joint all-time-leading goal-scorer in U.S. men's national team history. At the start of halftime, Donovan spoke with officials and with Phoenix manager Rick Schantz and said he asked for Flemmings to be removed from the game.
After the Loyal came back out for the second half and saw Flemmings was still in the game, the San Diego players all took a knee when the whistle blew, then walked off the pitch a few seconds later and never returned.
Flemmings denied he made the slur in a statement, but was placed on administrative leave by the club. Schantz was also placed on leave, although the club said it is in relation to a USL investigation that is unrelated to the events in the San Diego match.
The league also decided the match would count as a forfeit by San Diego and a 3-0 win for Phoenix.
It was the second incident involving an opponent using a slur against a Loyal player this season.
On Sept. 23, LA Galaxy II defender Omar Ontiveros used a racial slur against the Loyal's Elijah Martin (not related to Collin), a Black player. The Loyal earned a point for a draw in that game, but two days later the club announced it would forfeit that point. Ontiveros was released by the LA Galaxy II.
"With the support of the USLPA and the USLBPA, the United Soccer League announced last Thursday a partnership with The Institute for Sport and Social Justice which will see The Institute provide league-wide sensitivity training and education for all staff and players ahead of the 2021 season," Tuesday's announcement added.
ESPN's Jeff Carlisle and Reuters contributed to this report.