I had the same problem and posted for help from seasoned Yorkie parents as well. I was given some really good advice which worked for me so I'll share what I was told...
Put your baby on a surface that doesn't equal playtime, for instance the bathroom counter or on top of the washing machine. Hold treats in your hand to get their attention off the brush. Like suggested in one of the replies I wouldn't given it to them automatically, just give little bites at a time. With Winston, this helped tremendously. He is still a pistol and we have a lot of work to do still but this at least saves my hands and the brush from being chewed up. One other thing I try is to hold his nose in my cupped hand so he knows to stay still (sometimes this works and others it doesn't).
Also, try and do it more often, they really do get use to it.
Good Luck! I feel your pain
