Rebounds can become prime opportunities to score in hockey. They come right after a shot hits the goalie. The puck is saved but it bounces out, but usually not far from the goalie. Because the goalie got into one position to make the save, he can be completely vulnerable should the opposition get to that rebounded puck, depending on where the puck and player are. They may not be physically able to make a stop on a rebound. Defensemen and defending forwards are often present in the slot or around the crease to make sure those second (or third, or fourth, etc.