Floyd Mayweather Jr fears Ricky Hatton will never be the same fighter following his two knockout defeats and must retire immediately.

Hatton crashed to his first career loss to Mayweather two years ago, succumbing in the 10th round, and was battered inside two by Manny Pacquiao earlier this month.

No decision has been made on Hatton's future but Mayweather, who meets Juan Manuel Marquez in Las Vegas on 18 July, has urged him to hang up his gloves.

"Ricky's career was over in 2007 when he met me," said Mayweather.

"He was a gutsy, tough champ but there's a time in every boxer's career when they must hang it up. He was knocked out bad twice - by me and Pacquiao. They were two devastating defeats. He's been in a lot of tough fights and taken some big shots.

"I don't think Ricky should fight again. I wouldn't fight him, even at Wembley. It would be like picking on a guy that we call 'gun-shot'."

Mayweather rejected criticism of his decision to fight lightweight champion Marquez at a catch weight of 143lbs by claiming the Mexican should have beaten Pacquiao. In two contests against the Filipino, he drew the first and lost a controversial split decision in the second.

"I believe Marquez beat Manny twice. Marquez is a warrior and a great champion," said Mayweather.

"It's not a weight thing. Everybody's forgetting where I came from - I started a lot lower than 143."