Sopoaga's Highlanders team-mate Malakai Fekitoa posted a photo of Fekitoa being kissed by two of his team-mates on Instagram and Sopoaga commented "hah gayyyyyyyyyyye".
That may have been a reference to the internet meme which spawned from the television show Community, but it didn't go down well.
Sopoaga deleted the off-the-cuff comment and apologized immediately once he realised he may have upset people.
"Sorry to anyone who took offence to my comment above," Sopoaga wrote.