First off I'm new to this, andthis is the first dog I have ever trained to this extent. And I'm running into a problem. I have tought him to run a straight line to a pile that he knows at about 100 yds. He knows his left right and back on the baseball drill. My problem starts on running a true blind. He wants to start guessing or going to where he knows there is a bumper and not mark on the one I need him to. He tries to do good and to please me. I just cannot figure out how to get him to understand what I'm wanting. He is about to make me pull my hair out. Thanks for the advice.