A super middleweight bout featuring South African Thomas “Tommy Gun” Oosthuizen and Brandon “Flawless” Gonzales, of Sacramento, Calif., and a junior middleweight matchup between Cleveland’s Willie “The Great” Nelson and Argentine Luciano “El Principito” Cuello will be included on the undercard to Saturday night’s HBO-televised main event between WBA middleweight titleholder Gennady Golovkin and Matthew Macklin.

Oosthuizen (21-0-1, 13 knockouts), 25, was last in the ring for a unanimous decision over Fulgencio Zuniga, and also fought to a draw against current No. 8-rated light heavyweight Isaac Chilemba in 2010.

The Oosthuizen fight represents the first above eight rounds for Gonzales (17-0, 10 KOs), 29, whose most recent win was a decision over Don Mouton in Santa Fe, N.M.

Cuello (32-2, 16 KOs), 29, is riding a six-bout winning streak that includes four knockouts since falling by sixth-round knockout to Saul “Canelo” Alvarez in July of 2010. Cuello’s only other loss was by unanimous decision to Julio Cesar Chavez Jr. in March of 2009.

Nelson, 26, is currently rated No. 10 by THE RING at 154 pounds and has a record of 20-1-1 that includes 12 knockouts. He’s coming off a first-round knockout over Michael Medina in March.

Also on the card, junior welterweight Danny O’Connor (20-1, 7 KOs), of Framingham, Mass, will pursue his seventh straight win and his fifth knockout during that time against Hector Munoz (21-10-1, 14 KOs), of Albuquerque, N.M.

In addition, junior featherweight Luis Rosa Jr. (13-0, 6 KOs), of New Haven, Conn., will meet Mexico’s Jose Angel Beranza (36-26-2, 28 KOs), and junior middleweight Dusty Hernandez Harrison (15-0, 9 KOs), of Washington, D.C., will meet Ben Ankrah (17-15, 8 KOs), of Accra, Ghana.

Detroit junior middleweight prospect Tony Harrison (13-0, 10 KOs), a prot├®g├® of the late Emanuel Steward, will be matched against an opponent to be determined.

The Kazakhstan-born Golovkin (26-0, 23 KOs) most recently earned his thirteenth consecutive KO with a third-round knockout of Nobuhiro Ishida, who was stopped for the first time in his career. The win over Ishida followed Golovkin’s bloody, seventh-round stoppage of Gabriel Rosado at New York’s Madison Square Garden in January.

Macklin (29-4, 20 KOs) was last in the ring for September’s first-round stoppage of ex-titleholder Joachim Alcine after losing back-to-back fights against Sergio Martinez and Felix Sturm.

Lem Satterfield can be reached at [email protected]