Chad Grigg's light heavyweight debut is officially on hold.

That's because "The Grave Digger" is a little too banged up to fulfill his duties against Phil Davis at the UFC on FOX 4 event from the Staples Center in Los Angeles, Calif., on Aug. 4, 2012. The good news, is unbeaten prospect Wagner Prado has agreed to step in and take his place.

Davis (9-1) saw his undefeated record snapped by former division champion Rashad Evans earlier this year, in a bout where the NCAA Division I national champion wrestler out of Penn State was stymied across five rounds en route to a convincing unanimous decision loss.

Time to get back on the horse.

Prado (8-0) cut his teeth on the South American regional scene, racking up seven (T)KO wins in his eight fights and is one of the few Brazilians who comes into the Octagon without a single submission win. I guess you don't need to work the ground game when you're that good at knocking fools out.

"Mr. Wonderful," beware.

UFC on FOX 4 is expected to feature the recently announced middleweight bout of Hector Lombard vs. Brian Stann. Ryan Bader vs. Lyoto Machida, Terry Etim vs. Joe Lauzon, Oli Thompson vs. Philip De Fries and Rob Broughton vs. Matt Mitrione are also scheduled for the "City of Angels."

For the latest UFC on FOX 4 news and notes be sure to check out our complete event archive right here.