a dog and his lost ball

Gus is very particular about his balls. If Regis opens the trunk of the car to take one on a walk, he will get up and nose around to make sure it is the right ball. When they walk by the hospital, Gus loves to run into the meadow and drop his ball into one of the mounds made by whatever burrowing creatures lurk there. It's usually not a big deal because the hole isn't deep and Gus can retrieve it or Regis can snatch it with the ball toss thing. Not so the other day. Gus drops the ball into the hole, Regis tries to snag it, the hole is too deep...no ball. Gus in inconsolable. He won't leave the ball behind. Regis tries to walk on but Gus keeps running back to dig at the hole to retrieve his ball but no luck. Eventually they come home. The next day they take a garden trowel. I say to take a shovel but they don't listen to me. No ball can be found with the trowel. Gus is unhappy. This morning, finally, with the aid of a shovel and a bit of digging, the ball is unearthed. Gus is happy. A dog can't just chase any ball, you know.