He was running with it. He dropped it in the street just before he made the left head fake at the pick up and then hooked around to the right to attack the guy with the shotgun. When the camera seems to drift off to the right as the guy is following him down the street, he focuses on the hammer for a few seconds, they move the camera back to the left and back onto the move the guy made at the truck. He stole the hammer, dropped it, and then tried to get that guys shotgun away.
Either that, or he just normally carries a large hammer while hes running
Got it...thanks! Still not guilty IMHO. Everyone involved played a stupid game and won stupid prizes IMHO.