Be present, it is the only way to focus.
Depression is the past. Anxiety is the future. Be present to live your best life and play your best game. You cannot focus if you are not present in the current moment. Jack Nicklaus said "You can win tournaments when you're mechanical, but golf is a game of emotion and adjustment. If you're not aware of what's happening to your mind and your body when you're playing, you'll never be able to be the very best you can be." You can learn to be more aware and notice when you are getting distracted so that you can adjust.