Heading into his UFC on Fox 8 welterweight bout with Bobby Voelker, UFC veteran and perennial fan favorite Robbie Lawler had 20 career victories. Of those 20 victories, 17 came by way of knockout. After Saturday night, you can make that 21, as Lawler dispatched Voelker, leveling the Kansas City native with a thudding head-kick knockout at the start of the second round. Round one saw both fighters open with a purpose.  Lawler stalked his opponent with a cocked right hand, as the 34-year-old Voelker looked to earn his first victory inside the Octagon after failing in his debut against Patrick Cote at UFC 158. As Lawler pressured with a stiff jab, Voelker attempted to stymie the oncoming pressure of the former Miletich Fighting System product by using an array of leg kicks and lateral movement.