Serena Williams and Caroline Wozniacki have been inseparable lately. Whether it's the US Open final, the NY marathon, or a beach vacation, you can guarentee Caro and Serena will be there together.
Their Instagram feeds have been a little more saucy recently. The two have put aside the tennis shoes for bikinis... and they're really embracing the change! Check out the semi NSFW images after the cut!