Anthony Pettis is out of UFC 163 with a knee injury.
Pettis was slated to fight six-time defending UFC featherweight champion Jose Aldo in the main event of the Aug. 3 card in Rio de Janeiro, but had to succumb to the injury, UFC president Dana White announced via Twitter.
The Milwaukee native had won his previous three fights at lightweight, but was dropping down to 145 pounds to challenge Aldo.
The 26-year-old Brazilian Aldo (22-1) will now defend his belt against Chan Sung Jung, a.k.a. “The Korean Zombie.”
Jung, 26, is 13-3 and has won all three of his fights since joining the UFC.
