LONDON (Reuters) - WBA light-welterweight champion Amir Khan will take on IBF holder Zab Judah in a unification fight in Las Vegas on July 23, the Briton said on his Twitter page. July 23, WBA/IBF unification fight. KHAN vs JUDAH. Mandalay Bay, the 24-year-old former Olympic silver medalist, who beat Paul McCloskey in April, wrote. Khan won the WBA title against Andreas Kotelnik two years ago and has made four successful defenses, although his last two have been problematic. He came through a bruising encounter against Argentinas Marcos Maidana in December and then beat Northern Irishman McCloskey in April after his opponent suffered a bad cut in the sixth round after a clash of heads. Experienced American southpaw Judah, 33, reclaimed the vacant IBF title against Kaizer Mabuza in March.