American Sloane Stephens on Monday denied celebrating Serena Williams' shock exit from the Australian Open after she was filmed smiling and laughing as she watched on TV.
The relationship between the pair has been frosty since Stephens knocked world number one Serena out of last year's tournament in the quarter-finals.
Stephens later took aim at Serena for unfollowing her on Twitter and also reportedly accused the 17-time Grand Slam champion of ignoring her.
Local media seized on the footage of Stephens, filmed without her knowledge while was she was watching the Serena match and joking with hitting partner Andrew Fitzpatrick.
But Stephens said the two were merely mimicking the enthusiastic reaction of the coaches of Ana Ivanovic, the player who beat Serena on Sunday.
"At the end of the match, Ivanovic's coaches pretty much gave each other head-butts and kisses, and I thought that was the funniest thing ever because I have never seen a more excited head-butt/kiss at the end of the match," she told reporters.
"Then of course in posts and everything and edit and of course I'm cheering against Serena, which had nothing to do with it. So that was it. We were just having some fun."
The 20-year-old added that she felt the footage was intrusive.
"Yeah, it's a little much. Then for them to put it on TV was a little extra. It is what it is. I don't think it was that (big) a deal."