I don't think the fix was in Sponge; its just as has already been mentioned here--Shamrock is a cocky dumbphuk that isn't nearly as good now(or in the past) as he thinks he is.
I agree with the wease; I don't think that Frank's arm was that bad, he just got KTFO and wasn't about to go out for the 4th and go to sleep for real with another kick or six to his empty head.
And I always forget about how unbelievably BAD showtime's announcers are until the card starts. Then its mute the sound and sit back and enjoy the fights...