A statement from the club read: "The Gold Coast Suns are reviewing an incident between two players, Campbell Brown and Steven May, that took place in Los Angeles earlier this week following completion of a training camp in Arizona.
"The incident left May with a suspected fractured jaw which is expected to require surgery. No other players were involved.
"The club is in the process of establishing exactly what happened and all other relevant facts, and is discussing the matter with the two players concerned who have since returned to the Gold Coast ahead of their teammates.
"The GC Suns are considering appropriate actions and will not make further comment at this stage in relation to the incident."
Thirty-year-old Brown crossed to Gold Coast from Hawthorn after nine years and 159 matches for the Hawks.
Despite a chequered history with injuries and suspensions, he has played 46 matches and produced some quality performances for the Suns, especially during the 2013 season playing as a forward enforcer.