This was becoming clear even before the four homer game. His OPS was .982, for crying out loud. He had homered seven times in his previous 16 games. The gasps and whispers had already started.

In the 48 hours following Nick Kurtz's incredible accomplishment, here's a look at three recent sales of PSA 10 Rookie Autos.

Nick Kurtz became the first major league rookie to hit four homers in a game, leading the Athletics to a 15-3 victory over the Houston Astros