Male impala frequently spar by locking their horns in mock combat. But it's hard to know what is play and what is not. I watched this pair going at it with great intensity for fifteen minutes. It looked real enough to me. Because they moved behind the husk of a fallen tree, I could layer this image, sandwiching the battling impala between the gray tree in front of them, and the golden grass just beyond them. They seem to be fighting for territory, a space serving here as their own private corral between the old dead tree and the dead grass.