The rider must lasso the calf from horseback by throwing a loop of the lariat around the calf's neck. Once the rope is around the calf's neck, the roper signals the horse to stop quickly while he dismounts and runs to the calf. The calf must be stopped by the rope but cannot be thrown to the ground by the rope. If the calf falls, the roper loses seconds because he must allow the calf to get back on its feet. When the roper reaches the calf, he picks it up and flips it onto its side. Once the calf is on the ground, the roper ties three of the calf's legs together with a short rope known as a tie-down rope or "piggin' string". A half hitch knot is used, sometimes referred to colloquially as "two wraps and a hooey" or a "wrap and a slap". The piggin' string is often carried between the roper's teeth until he uses it. The horse is trained to assist the roper by slowly backing away from the calf to maintain a steady tension on the rope.