Has an AFL game ever ended 138-37?
Exactly once. On May 19, 2012, Sydney beat Melbourne 138-37, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 138-37 in league history.
That makes 138-37 the 3885th most common final score out of 6,649 that have ever occurred in AFL. One point away, 139-37 has happened never and 138-38 has happened never.