The rivalry started after Conor McGregor brought in Malignaggi to help him prepare to box Floyd Mayweather.
James takes on the experienced and durable former champion DeMarco in his fourth-straight appearance at The Armory in his hometown.
Leben was originally scheduled to face Brennan Ward, who was forced to withdraw from the event.
The event streams live on DAZN from Madison Square Garden in New York City.
Shevchenko scored her first title defense with a vicious head-kick knockout over Jessica Eye recently and has her sights set on more.
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Check out special "Countdown" videos featuring both Sonnen and Caldwell, who are in action this Friday night live on DAZN.
The former UFC champions will each be in separate bouts on the August card of ONE: Dawn of Heroes from the Philippines.
The broadcast starts at 8 p.m. ET/5 p.m. PT and features former world champion Andre Berto taking on Miguel Cruz in a 10-round welterweight clash.
SHOWTIME CHAMPIONSHIP BOXING begins at 9 p.m. ET/6 p.m. PT and will feature the youngest reigning American world champion in Davis.
TS-1 Promotions announced that it will bring the Combate Americas television series to Odessa, Texas for the first time ever with a stacked lineup
Premier Boxing Champions on FOX Sports Pay-Per-View on Saturday, July 20 from the MGM Grand Garden Arena in Las Vegas.
Top contender admits she made a mistake in championship match vs. Valentina Shevchenko this past weekend in Chicago at the United Center.
IBF Super Middleweight World Champion Caleb "Sweethands" Plant makes his first defense of his title against unbeaten contender Mike Lee.
The classic from 2009 will enter into the UFC's Hall of Fame this July during a special ceremony in Las Vegas from the same venue it took place in.
Ex-middleweight champion believes timing is right for move up to 205 pounds and the light heavyweight division for his next fight
The former UFC fighter claimed the LFA flyweight title with a fourth round TKO victory live on AXS TV.