Description: The Ultimate Fighting Championship makes its Philadelphia debut for UFC 101: Declaration, and in the main event, the two best 155-pound fighters in the world finally meet when UFC lightewight champion BJ Penn defends his crown against number one contender Kenny Florian. In the co-feature, the middleweight champion Anderson "The Spider" Silva, tests the waters at 205 pounds once again when he battles former light heavyweight champ and Ultimate Fighter season one winner Forrest Griffin in one of the most explosive fights of 2009.