To show his support for Floyd Mayweather Jr., Justin Bieber joined the undefeated American fighter during a photo opportunity after the press conference in Los Angeles for his upcoming fight against Manny Pacquiao. 

The 21-year-old singer, according to Daily Mail, could not help the urge to join Mayweather on the stage as cameras started taking photos of him and Manny Pacquiao.

Bieber is known to be a great supporter of Mayweather as he has attended most of the latter's fights in recent years, even joining his entourage in May 2012. He was also given the chance to hold Mayweather's WBC belts after the American boxer defeated Miguel Cotto at the MGM Grand Areana in Las Vegas.

According to Daily Mail, the boxer appeared prepared in a light grey suit for the event while Pacquiao sported a black suit and a white dress shirt.

During the press event, Mayweather said "the world will stop" during his fight with Pacquiao on May 2.

"May 2 - the world stops. Mayweather v Pacquiao is the biggest fight in history," Mayweather was quoted by BBC as saying.

The fighters had verbal exchanges during the press conference where they both declared that one is a greater fighter than the other.

"If you lose, it is always in your mind but I have to be thankful that we have all come together as one to give the world what they want to see," Mayweather told Pacquiao.

On his Twitter account, Pacquiao also had something to say about what is good for boxing with reference to Mayweather.

"Beating Floyd is good for boxing. When athletes have great success, their success goes to their head. That is bad for boxing. I'm here to prove that I can easily beat the undefeated," Pacman said on his social media account.

People are still divided on who will emerge as the clear winner of the game as Pacquiao's speed and power will go against Mayweather's supreme defensive skills.

"My footwork and hand combinations will be my advantage. I tell you Miguel Cotto and Antonio Margarito punch hard. This is boxing and its about punches," this what Pacquiao boasted on his Twitter account.

Daily Mail also quoted Freddie Roach, who said that they may be fighting the best fighter in the world but he assured that they will "kick his ass."

"My guy is too fast, he hits too hard. I think Floyd's legs are shot. He says he wants to stand and trade more and entertain the fans more, but I don't think that is true. He has to say that," Roach added.