UFC officials confirmed the fight with ESPN.com on Tuesday.
Escudero replaces T.J. Grant, who suffered an injury that forced him to withdraw from the bout. The nature of Grant’s injury has not yet been revealed.
Escudero, "The Ultimate Fighter" Season 8 lightweight winner, was released by UFC in September 2010 after a submission loss to Charles Oliveira. Before that fight, Escudero weighed in three pounds above the required limit and sacrificed 20 percent of his purse.
Since his release, Escudero has won five of his six fights for an overall record of 18-3.
Volkmann (13-2) has won all four of his fights since debuting at 155 pounds in March 2010. He began his professional MMA career at welterweight.
The Lesnar-Overeem winner gets a shot at current heavyweight champion Junior dos Santos.