Lopez, 31, of Puerto Rico, seemingly resurrected his career in March when he knocked out former two-division titleholder Daniel Ponce De Leon, but it was a mirage. Ponce De Leon was just as faded as Lopez and retired after the fight. Lopez, a southpaw and former junior featherweight and featherweight titleholder, might be on his way to joining him after taking a beating from Vargas, 29, a 2008 Mexican Olympian who is managed by Joel De La Hoya, promoter Oscar De La Hoya's brother. Lopez has been knocked out in all four of his defeats.
• Mauricio Herrera (21-4, 7 KOs), fighting for the first time since his controversial March 15 majority decision loss to unified junior welterweight champion Danny Garcia, won an interim junior welterweight title against Johan Perez (19-2-1, 13 KOs) in an action-packed fight.
Although Herrera seemed to get the better of Perez for most of the fight it was a highly entertaining affair throughout, one he won on scores of 116-112 and 116-112 while the third judge scored it 114-114.
"It was difficult at first because of his awkward style," Herrera said. "It took me a minute to get used to his style. At first he was making me miss a lot of my shots but then, after I relaxed and adjusted to his style, I was able to take control and put more pressure on him. I felt like I was the hungrier fighter in there tonight."
Herrera, 34, of Riverside, California, and the crowd favorite, rocked Perez, who was making his second defense, with a booming right hand in the fifth round, but it was just before the bell and he did not have the opportunity to follow up.
The eighth round brought the crowd to its feet as the fighters spent a long period of the round in a wild toe-to-toe exchange in the middle of the ring. A hard right hand just before the bell ended the 11th round rocked Perez, 31, of Venezuela, again.
"Herrera had a difficult style. I thought it was a close fight but I felt I won it. I'm really surprised by the decision and I would like an immediate rematch," Perez said through a translator.
• Bantamweight Tomoki Kameda (30-0, 19 KOs) celebrated his 23rd birthday with a one-punch knockout of mandatory challenger Pungluang Sor Singyu (46-3, 31 KOs) in the seventh round to retain his world title for the second time. Japan's Kameda, who is based in Mexico and fights out of the Canelo Promotions stable, had the distinct speed advantage and also boxed and moved well, touching Sor Singyu with punches and moving away without taking much in return. But Sor Singyu, 26, of Thailand, continued to barrel ahead and stunned Kameda with a hard right hand in the fourth round. He also attacked Kameda to the body. But Kameda routinely beat Sor Singyu to the punch and moved side to side, which Sor Singyu could not deal with. In the seventh round, Kameda landed a pinpoint left hook to the liver and Sor Singyu dropped to the canvas immediately. He was writhing in pain as referee Russell Mora called it off at 1 minute, 35 seconds.
• Southpaw middleweight Yamaguchi Falcao (2-0, 1 KOs), a 2012 Olympic bronze medalist from Brazil now living in Los Angeles, stopped Puerto Rico's Jesus M. Cruz (1-2-1, 0 KOs), who retired on his stool after the third round of a one-sided fight.