LOS ANGELES - Popular Mexican superstar and former middleweight champion Julio Cesar Chavez Jr. and dangerous brawler Andrzej Fonfara participated in the final the final press conference Thursday at Crowne Plaza Hotel LAX, just two days before Saturday's SHOWTIME CHAMPIONSHIP BOXING doubleheader.

Chavez (48-1-1, 32 KOs) of Culiacan, Mexico, and Fonfara (26-3, 15 KOs) of Chicago by way of Radon, Poland, will meet in the 12-round light heavyweight main event live on SHOWTIME CHAMPIONSHIP BOXING (10 p.m. ET/ 7 p.m. PT) from StubHub Center in Carson, Calif.  Chavez will make his eagerly awaited return to the ring and first start for new trainer Joe Goossen.

Also participating in today's press conference was undefeated top 10-ranked super lightweight Amir Imam (16-0, 14 KOs), of Davie, Fla., by way of Albany, N.Y. who will put his unblemished record on the line against fellow power-puncher Walter Castillo (25-2, 18 KOs) (25-2, 18 KOs), of Managua, Nicaragua, in the 10-round co-feature on SHOWTIME.

On SHOWTIME EXTREME® (8 p.m. ET/PT) this Saturday, WBA Interim Super Bantamweight World Champion Oscar Escandon (24-1, 16 KOs), of Tolima, Colombia, will make the first defense of his 122-pound title when he faces undefeated Moises "El Chucky" Flores (22-0, 1 NC, 16 KOs), of Guadalajara, Mexico. 

In the SHOWTIME EXTREME co-feature, Omar "El Businessman" Chavez (32-3-1, 22 KOs), of Culiacan, the younger brother of Chavez, Jr. and son of legendary Julio Cesar Sr., will face Richard Gutierrez (28-15-1, 17 KOs), of Arjona, Colombia, in an eight-round middleweight fight. Also featured on the telecast, time permitting, will be a six-round match between unbeaten Argentine welterweight Fabian "TNT" Maidana, of Santa Fe, Argentina, the brother of former world champion Marcos Maidana, who'll be opposed by Cory Vom Baur (2-2, 0 KOs), of Vancouver, Wash.