Former world champion Amir Khan will meet American Luis Collazo on the undercard of Floyd Mayweather's bout with Marcos Maidana on 3 May.
Khan has not fought since a points win over Julio Diaz in Sheffield last April but will make his welterweight debut against Collazo in Las Vegas.
"You'll see a different fighter - better, more skilled, patient and smarter," said Bolton-born Khan, 27.
"I can't wait to get back in there and cause some hurt."
Khan had hoped to fight WBC welterweight champion Mayweather at the MGM Arena, but the 37-year-old American, a 10-time world champion, chose to fight Maidana instead.
"I think the fight with Mayweather will happen one day but I'm not rushing and it will happen when I'm ready," said Khan.
Argentine Maidana, 30, is the WBA welterweight champion but was beaten by Khan on points in 2010.