Think process over outcome.  Neurolinguistic programming helps here.  Focus on what you need to do to get to where you want to be, baby steps.  If you go into a match thinking you are going to give 100% and may win and may lose but are committed then there is less chance for choking.  If you have practiced a ton that helps too.  Usually shots that are mechanically unsound are the ones that break down under pressure.  Some athletes Thrive under pressure.  Michael Jordan is a prime example.  He wasn't afraid to lose- he was thinking process over outcome I bet.

 If The Fed choked, it's uncommon.  Remember how many consecutive finals he won.  It may have happened but it is uncommon for him.

 When you point out that everybody has choked, don't forget to point out that everybody has lost too.