According to ESPN, Charlie Batch has the highest single game QBR
rating of all time -- a perfect 100.  That was in September-
12/17, 186 yards, 10.9 AVG, 3 TD, 2 INT  Since then ESPN changed
that rating (I assume because of embarrassment since anyone who
knows anything can tell you that's not a spectacular game,
certainly not the best ever.)  The reason the QBR rating is not
immediately available during and after the game like passer
rating is because analysts go through the film and make
determinations on who is at fault for missed passes etc.
 Something they could not know without knowing the play.    QBR
is an opinion, not a statistic.