There's only one legitimate place I've found to watch it, the rest seem like scams :-/ You can see it over here though: http://unlocksports.com/watch28015.html

They make you do a little survey but after that it's good to go

This is one of the only sites I've found that works:
http://sportssvideoss.blogspot.com/

It asks you to do a survey but then it should take you right to the match! Enjoy

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http://www.webhush.com/watch-ufc-100-live-streaming-online-free/