Overeem has great takedown defense and good grappling and ability to get to his feet. I doubt Stipe can get Reem down or hold him there. And Stipe fancies himself a striker so I figure he will look to try and beat Reem on the feet. Which is exactly why Overeem should throw off Stipe's game. Kicks his legs and take his ass down, take him down as much as you can and try and keep him down. Reem has good ground and pound and decent takedowns. If he could hold Stipe down or just damage Stipe enough and tire him out in the clinch and via takedowns it will take a lot of Stipe energy away.