Justin Thomas has apologised after he was heard using a homophobic slur during his third round at the Tournament of Champions in Hawaii on Saturday night.
The number three golfer in the world was playing the fourth hole and missed a five-foot putt for bogey before making uttering the offensive word which was picked up by television microphones on the course.
Thomas spoke to the Golf Channel at the end of his round and made an apology for the comment.
"It's inexcusable. First off, I'll just apologise. There’s just no excuse," said the defending champion at the event.
"I’m an adult. I’m a grown man. There’s absolutely no reason for me to say anything like that. It’s terrible. I’m extremely embarrassed.
"It’s not who I am. It’s not the kind of person that I am but, unfortunately, I did it and I have to own up to it and I’m very apologetic."
Thomas revealed that he was unaware that the slur had been picked up on microphone and was a topic on social media until after he had finished playing.
“I’m speechless. I found out when I got done on the golf course, when I got done with my round," added Thomas.
"It’s bad. There’s no other way to put it. I need to do better. I need to be better. It’s definitely a learning experience.
"I deeply apologise to anyone and everybody who I offended and I’ll be better because of it."
The PGA Tour never discloses the details of any conduct punishments for golfers but it is expected that the 26-year-old will receive a fine for conduct unbecoming of a professional.
They released a statement which read: "As he expressed after his round, we agree that Justin's comment was unacceptable."
Thomas shot a five-under par 68 to lie four shots off the lead in Hawaii.
American duo Harris English and Ryan Palmer share the lead going into the final round, tied on 21 under par after day three.
Third placed Colin Moriwaka is just one shot behind them.