Blind dog playing fetch

This English Springer Spaniel named Kellar was born blind, but he isn't the type of dog to roll over when things get ruff rough. He uses his sense of hearing along with verbal cues from his owner to find his toy.

According to the video:
Kellar was originally trained to play ball with the commands "hot" and "cold". We later added "warmer", "passed it", "left" and "right". The process took about a week for the basic commands.