The Octagon is at the Enterprise Center in St. Louis, Missouri for tonight’s UFC on ESPN 56 event.  The fight card is headlined by a heavyweight bout between knockout artist Derrick Lewis and 15th-ranked Rodrigo Nascimento. Lewis (27-12, 1 NC) will enter the match coming off a decision loss to Jailton Almeida in his last fight.   Lewis, ranked 12th in the division, has lost four of his last five fights and desperately needs a win to stay relevant in the weight class.    Nascimento (11-1, 1 NC) is riding a three-fight winner streak and looking to take out his highest profile opponent