Freddie Roach on Killer Instinct

Freddie Roach, who has worked with Georges St-Pierre, Anderson Silva, and Mauricio "Shogun" Rua, as well as great boxers such as Manny Pacquiao, has the following to say on killer instinct:

One thing about fighters, we have to have a killer instinct. If we hurt somebody we know to go for the kill. For the wolf it's live or die, and for us in the ring it's live or die.

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This quote is excerpted from the documentary "The DNA of GSP", which is expected to come out in October 2013, and is directed by Kristian Manchester and Peter Svatek