Mike Chiappetta • E-mail

Renato "Babalu" Sobral will get a crack at the Strikeforce light-heavyweight championship when he takes on Bobby Southworth at the organization's "Strikeforce at the Mansion II" show on Sept. 20, a source told NBCSports.com.

The match could be officially announced as early as this afternoon, according to the source.

Sobral signed with the company last year, but will be making his debut in the organization.

The 33-year-old Brazilian is one of the most highly regarded light-heavyweights in the world and once faced Chuck Liddell for the UFC light-heavyweight championship. He is currently riding a three-fight win streak, most recently defeating Mike Whitehead via unanimous decision during July's Affliction: Banned event.

Sobral was expected to face off with Tito Ortiz at the second Affliction event, which will take place on Oct. 11, but with just three weeks between shows, that seems highly unlikely.

Southworth captured the Strikeforce light-heavyweight title with a win over Vernon "Tiger" White in December 2006. He most recently defended the belt with a five-round unanimous decision over Anthony Ruiz in June.

Along with that main event, Japanese star Kazuo Misaki will make his Strikeforce debut, challenging Joe "Diesel" Riggs.

Misaki, a former PRIDE welterweight Grand Prix winner, holds wins over standouts such as Dan Henderson and Denis Kang on his resume.

Riggs, a former UFC star, holds wins over Nick Diaz, Chris Lytle and Kendall Grove in his career.

Last year’s Playboy Mansion show drew a star-studded crowd including Hugh Hefner and the “Girls Next Door,” actors Michael Clarke Duncan and Jaime Pressley and several MMA notables. Television broadcast information is not yet available, but for ticket information, see the Strikeforce website.

Last year’s Playboy Mansion show drew a star-studded crowd including Hugh Hefner and the “Girls Next Door,” actors Michael Clarke Duncan and Jaime Pressley and several MMA notables. Television broadcast information is not yet available, but for ticket information, see the Strikeforce website.