For the record, I believe Farnsworth has tackled two people in his major league career in two separate incidents. Hence the confusion.
That is too funny.. Farnsworth is the man..
Seconded, I don't know anything about an Affeldt (Jeremy Affeldt?) fight, but I can't get the image of Sean Casey staggering back to the dugout bloodied out of my head. Farnsworth was a Cub and Casey was a Red, I'm pretty sure it was '04. And Casey's not a little guy either.
EDIT: I'm wrong, Sean Casey was not involved in the fight I'm think of. And it was '03. http://www.cincypost.com/2003/06/20/reds06-20-2003.html
Here's the link. It was pitcher Paul Wilson. Kinda looks like Casey though...
But the conclusion that you don't mess with Kyle Farnsworth remains true, despite the false premises.