Has an AFL game ever ended 54-51?
Yes. AFL has seen a final score of 54-51 5 times. It first happened on July 1, 1905, when St Kilda beat Melbourne, and most recently on August 21, 2010, when Collingwood beat Adelaide.
That makes 54-51 the 589th most common final score out of 6,607 that have ever occurred in AFL. One point away, 55-51 has happened 4 times and 54-52 has happened 2 times. At one point the score disappeared for 55 years, between 1912 and 1967.