English lightweight Terry Etim is the latest fighter to succumb to the injury bug.

An undisclosed injury forced Etim out of his UFC on FOX 4 clash against Joe Lauzon, UFC officials announced earlier this week. Reinvigorated former WEC champion Jamie Varner has been tapped to fill the vacant spot.

UFC on FOX 4 is slated for August 4, 2012 at the Staples Center in Los Angeles, CA. Lauzon vs. Etim was previously slotted on the FOX televised main card, which is headlined by a light heavyweight match-up pitting Mauricio Rua against Brandon Vera.

Varner (20-6-1, 2 NC) enters the bout on short notice after pushing his winning streak to three straight with a first-round knockout over highly-touted Brazilian prospect Edson Barboza at UFC 146. The upset marked the 27-year-old's first fight in the UFC since 2007.

Across the cage, Lauzon (21-7), the owner of seven post-fight UFC bonuses, looks to rebound from a devastating head kick knockout loss Anthony Pettis. Prior to the setback, "J-Lau" rolled to a consecutive first-round submission finishes of Melvin Guillard and Curt Warburton.