NSW Waratahs say they are disappointed to hear of an allegation of racist behaviour towards Hurricanes forward Du'Plessis Kirifi following the home side's 22-18 defeat at Leichhardt Oval on Saturday night.
Kirifi took to Instagram on Monday afternoon, apologising for a picture that showed him giving the one-fingered salute to members of the crowd after the Hurricanes' win on Saturday night.
While not excusing his behaviour, Kirifi said a line had been crossed by members of the crowd who taunted him with racial slurs and referenced his mother.
"I love the arena, I love to compete alongside my teammates and I love when the crowds are hyped and throw chat from the stands, " Kirifi wrote on Instagram. "But there's a line and just because you're in the crowd doesn't give you the right to talk about my mother or my race.
"Abuse from the sideline is part of our job, and it's a part I personally love - however this doesn't justify racial slurs or comments about my family.
"I passionately wear my heart on my sleeve but I'm [nowhere] near perfect. I admire my teammates who are mature enough to be non-reactive and hopefully the next time I'm in this position I show some resolve.
"As athletes we're in the public eye so I apologies to anyone disappointed by my actions, especially those with kids who look up to us as professionals. If I had my time again I'd definitely act in a different way."
In a statement provided to ESPN, NSW Waratahs condemned the alleged abuse, saying inclusiveness was an inherent value of rugby.
"The NSW Waratahs are disappointed to be recently made aware of an allegation of racial abuse from the crowd at Leichhardt Oval towards Hurricanes player Du'Plessis Kirifi on Saturday night," the statement read.
"There is no place for racism in society and this behaviour will not be tolerated.
"The NSW Waratahs celebrate the multicultural diversity of our team and are proud to embrace the inclusiveness of all cultures and races in rugby."
The allegation has taken the shine of a successful stint for the Waratahs at Leichhardt Oval this year, the venue clearly resonating with Sydney rugby fans given back-to-back crowds in excess of 10,000 people.
The club last week called on supporters to "fill the hill" on the eastern side of the venue, and they almost did with only a small area of the embankment empty.
ESPN has reached out for comment from the Hurricanes while the Waratahs say no formal complaint has yet been raised.
NSW head to Dunedin to face the Highlanders this weekend before returning to Leichhardt Oval for their final regular season game against the Blues.