If any of you have previously restrained your Yorkie from a "chase", please consider how you might do that safely (long leash/confined area).
The probability of an actual "catch" is unlikely, our little guys just aren't quick enough to do that usually. (possible for those who are well practiced and in very good shape).
This natural activity is really good for them psychologically and physically.
(remember to praise them highly, even when they miss)