What you have right now is we used to call a "gamer" on your hands. They thrive on direct competition. She felt a competition with that particular player. What we have found out that is unlike the theories the old days is players can change. They don't have to stay that way. The key is to...
Typically uncertainty & unpreparedness is the reasons for a lack of confidence. First get her mind focused on execution and off of results. (Focus on the process). Win and losing don't matter and will take care of itself. 2nd how much has she been practicing and have you had her practice in...