Floyd Mayweather said in an interview with Showtime's Jim Gray that he has lost respect for Manny Pacquiao.
Mayweather defeated Pacquiao by unanimous decision in their long-awaited fight in Las Vegas on May 2. He later sent a text to ESPN's Stephen A. Smith earlier this week saying he would be willing to give Pacquiao a rematch.
In the interview, Mayweather reportedly said he's changed his mind about a rematch and called Pacquiao a "coward" and a "sore loser."
After the fight, Pacquiao revealed that he was dealing with a shoulder injury. He will likely be out of action for the next 9-12 months after he has surgery to repair a tear in his right rotator cuff, but Top Rank promoter Bob Arum had said Pacquiao would be up for a rematch with Mayweather next year.
Asked for his assessment of Pacquiao and his shoulder injury, Mayweather said in the interview, "He's embarrassed. He was a beat fighter."
Mayweather added that he knew "excuses" would be made after the fight.
"I'm not going to buy into the bull----," Mayweather said. "I'm not going to buy into the bull----, and I don't want the public to buy into the bull----. He lost, he knows he lost, and I lost a lot of respect for him after all of this."
Mayweather, 38, has never lost a fight in 48 tries as a professional. He said after Saturday's bout that he will fight once more in September and "then it's time for me to hang it up."
"I won, I know I won, I know I'm the better fighter," Mayweather said in the interview. "We fight 10 times, I'm going to win 10 times; we fight 20 times, I'm going to win 20 times; we fight 100 times, I'm going to win 100 times.
"Manny Pacquiao, just, he's not a better fighter than me."
The complete interview airs Saturday night on Showtime.