Leading 3-1 and with a play-off position on the line, USL Championship - the second tier of football in the United States - club San Diego Loyal abandoned its match against Phoenix Rising after openly-gay midfielder Collin Martin received a homophobic slur from one of his opponents. 

Martin claimed the slur, uttered during a tense exchange with Rising's Junior Flemmings, was the first he had received on the pitch in a professional career spanning eight years.

The 25 year-old, who has played for DC United and Minnesota United in the MLS, was shown a red card after the confrontation with Flemmings, the referee having mistakenly assumed Martin was directing abuse at him.

Loyal, coached by former United States star Landon Donovan, refused to finish the match, surrendering the chance to secure a spot in the USL play-offs in a powerful statement against discrimination. 

"They will remember that they stood up for something they believe in," Donovon said. "You can't claim that you have these values if you don't act when it really matters."