Floyd Mayweather Jr has said that he is backing Serena Williams to win the US Open and complete a Grand Slam.

Williams is looking to become the first player since 1998 to win all four major titles in one year.

However, Mayweather is confident that the 21-time Grand Slam champion is capable of winning and breaking more records in the future.

He told reporters: "I'm very pleased with Serena Williams. They say records are made to be broken.

"I'm just very proud of her and what she's done during her career. She's done some amazing things in her career. It's just marvellous what she did.

"I'm behind her 100%. If she stays focused she can continue to break records."

Victory at Flushing Meadows would draw Williams level with Steffi Graf on the all-time list of Grand Slam winners.