I have this friend of mine who is obsessed with tennis. However, he has the most narrow-minded and ignorant view on tennis EVER. He only believes what he thinks is true and refuses to consider any advice given by people (nor mine) on how to improve. I constantly give him advice but his reply is always, "I don't need it, I just need to hit". He does not have any of the proper fundementals down at all and is simply the learn-on-his-own player. The only person who hits with him frequently is me. I usually do not mind hitting with him, but the gap is getting way too big. Also, tennis tryouts are less than a month away. I can't get any practice hitting with him, he's simply the most stubborn player I know. I want to practice with others without him being there to downplay the competitive atmosphere, but I don't want to hurt our friendship either. What should I do?