My dog Billy always shoots off to get his stick when I throw it, despite me trying to get him to stay still until commanded to fetch. What's the best way to keep him still even after I've thrown the stick?
Does your dog have a BASIC stay? (I do NOT mean holding a stay while you throw the toy). What I would do, in that case, is put the dog in a sit stay, walk out a few steps, and PLACE the ball or stick on the ground. Walk back and release him to get it. When he masters this, the ngo to walking out and dropping the ball or stick, then walking out and tossing it gently a few steps in front of you, etc- basically, take things in tiny steps.
Could be worse. When Zero gets tired of playing fetch he will run full blast after the tennis ball, sniff it, then come back with nothing and look at me as if he's expecting me to throw something else.
First, the dog has to have a good enough sit/stay that you can be sure he understands. This means the dog will hold "sit" in the face of at least mild distractions, while you walk to the length of his 6 ft. lead.
With the dog at "sit" you throw the retrieve object a short distance (3-4 ft.). If the dog begins to break, you reinforce the "sit" however you do it. I use leash corrections, but the hand and body blocks work well. You want to reinforce the "sit" right when he begins to break. That's the split second he begins to shift his weight forward.
For every 4 or 5 throws, you let the dog retrieve the object once. The other 75-80% of the time, you walk out and pick it up yourself. Don't let the dog identify a pattern in this drill. As the dog's steadiness improves, you make longer and longer throws. The retrieve becomes the reward for obedience. This not only develops steadiness, it can increase drive in some dogs.