Amir Khan will defend his WBA 140-pound title on Dec. 11 in the British champion's debut in Las Vegas. Golden Boy Promotions formally announced Thursday that Khan will meet Argentina's Marcos Maidana at the Mandalay Bay Events Center. Khan won a silver medal at the Athens Olympics and has evolved into a star, claiming a world title with a victory over Andreas Kotelnik last year. He defended his belt in New York last May, stopping Paulie Malignaggi in the 11th round. Khan has been eager to fight in boxing's capital city for several years, hoping to raise his international profile.