Floyd Mayweather will face Miguel Cotto for the WBA light-middleweight title in Las Vegas on May 5, it has been confirmed.
Recent reports had suggested that Mayweather would face Pacquaio but the organisation of the Cotto fight has ended such speculation.
"Miguel Cotto is a world-class fighter who can never be taken for granted and continues to prove he is one of the best in boxing," Mayweather said.
"I have no doubt in my mind that my title belt collection will increase once again."
The 34-year-old is due to serve an 87-day prison sentence beginning on June 1 for a domestic violence conviction.