Keith Thurman will be back in the main event of a Showtime-televised triple-header from the StubHub Center in Carson, California, as the welterweight prospect/contender will face former lightweight titleholder Julio Diaz. On the undercard, Lucas Matthysse will take on John Molina, and Omar Figueroa will face Jerry Belmontes.

Thurman (22-0, 20 KO) is coming off of a TKO-9 win over Jesus Soto Karass in December, and the fight with Diaz (40-9-1, 29 KO) is a sideways step at best. The 34-year-old Diaz is 0-2-1 in his last three fights, drawing with Shawn Porter, then losing a close fight with Amir Khan, and a rematch with Porter that the younger man handled fairly easily.

Matthysse (34-3, 32 KO) is looking to rebound from his September 2013 loss to Danny Garcia and get back on track in the 140-pound division. Molina (27-3, 22 KO) had recently been in discussions to face Adrien Broner on May 3, but it now appears Broner will face Carlos Molina (the lightweight) instead. Molina, 31, has a flair for the dramatic, with rally KO wins against Hank Lundy and Mickey Bey Jr to his credit, but he was also blown out in 44 seconds by Antonio DeMarco in 2012.

Figueroa (22-0-1, 17 KO) will be back for the first time since his July 2013 domination of Nihito Arakawa, a fight that may have done more damage to its near-shutout winner than the losing man, who took an awful beating. Figueroa has been bothered by hand injuries from that fight, and was recently scrapped from the Canelo-Angulo PPV card. Belmontes (19-3, 5 KO) is a spoiler type fighter who recently "upset" Will Tomlinson on March 8.