Sao Paolo, Brasil (CNN) - Yes, you can teach an old dog new tricks!
Four shelter dogs rescued from the slums and abandoned lots around Sao Paulo, Brazil was trained at "ball dogs" for the Brazil Open Tournament.
They retrieved balls that went out of bounds at an exhibition match, then they were supposed to give them back to the players. They really didn't like that part at all. The idea came from a local shelter that helped to raise awareness for the strays and shelter dogs in the area. The dogs also took part in the awards ceremony.