Chael Sonnen has found a new calling.| Photo: Dave Mandel/Sherdog.com

Less than a month after retiring from mixed martial arts, Chael Sonnen will make his debut for Brazilian jiu-jitsu promotion Metamoris on Aug. 9.On Thursday, the Los Angeles-based promotion announced its full slate of matches for Metamoris 4. In the evening’s main event, Sonnen will take on former Strikeforce fighter Andre Galvao . Also making his debut will be current Ultimate Fighting Championship fighter Josh Barnett , who will face Dean Lister for the promotion’s inaugural heavyweight title.Grand Slam jiu-jistu champion Keenan Cornelius will finally take on Vinny Magalhaes in a bout that was supposed to take place at Metamoris 3. Rounding out the slate of six matches will be Saulo Ribeiro versus Rodrigo Medeiros and Garry Tonon vs. Kit Dale. There will also be a “secret match” that will be revealed the night of the event.For Sonnen, the bout will serve as a substitute for what was supposed to be a UFC tilt against Vitor Belfort at UFC 175 on July 5. Following a failed drug test, the former middleweight No. 1 contender retired from competition.Sonnen’s opponent fought seven times as a mixed martial artist (5-2), but is widely acclaimed for his credentials in the grappling world. Galvao is a former Abu Dhabi Combat Club champion in the absolute division.Lister will return to the mat following a match at Metamoris 3 with Renato Sobral , this time looking to claim the promotion’s title at the expense of a debuting Barnett. “The Warmaster” was last seen in action at UFC 168 in December, when he lost to Travis Browne via brutal knockout.Metamoris 4 will take place at the Peterson Automotive Museum in Los Angeles, and will be available to stream via pay-per-view on Metamoris.com.