Revealing mistake: When Ajax slams the hammer end of his spear into a man, he has his shield at his back. The top arrow in the shield is bent at a 90° angle and as Ajax moves the top (plastic) arrow droops down and the bottom arrow actually flops around. While still in the same location, when he sticks his spear into the sand and pulls the arrow out of his thigh, the arrows on his shield are gone. (00:42:20)
Continuity mistake: The fan who came out onto the ice and draped a flag around Jim Craig's shoulders (a cameo by the film's director, by the way) put it on upside-down. The camera cuts away, then cuts back, and it's suddenly right-side up.