Floyd Mayweather Jnr celebrates win over Marcos Maidana with Justin Bieber

Floyd Mayweather Jnr had Canadian popstar Justin Bieber by his side in Las Vegas following his victory over Marcos Maidana.

The US boxing champion added the WBA world welterweight title to his WBC belt courtesy of a majority decision victory on Saturday night.

After the bout, Bieber joined Mayweather in the ring at the MGM Grand Garden Arena, taking a selfie which he posted on Instagram with the message: "He can't lose â™› love u champ."

Mayweather is unbeaten in 46 professional fights.