Justin Beiber, Lil Wayne, Floyd Mayweather and 50 Cent
Justin Bieber and Lil Wayne represent just a small section of the unique assortment of stars that come together to watch a high-profile professional fight.
From movie stars and chart-topping musicians to politicians and businessmen, not many escape the allure of the ringside seat.
Whether at the Dallas Cowboys Stadium, the MGM Grand in Las Vegas or Madison Square Garden, the atmosphere becomes thick and magnetic for the important and hyped megafights.
Here are the biggest celebrity boxing fans on fight night.
Jay-Z is not just a rap music mogul, but a rather focused boxing fan in this picture.
Here, he is attending Floyd Mayweather's split decision win over Oscar De La Hoya in May 2007.
Rap mogul Diddy checks the Shane Mosley vs. Floyd Mayweather fight.
He seems disappointed that Mayweather survived that scary second-round heavy hit from Mosley.
Did Diddy have any money on an upset? You don't bet against Mayweather.
Mariah Carey and Nick Cannon
Multi-platinum selling recording artist Mariah Carey is with her hubby Nick Cannon to see Ricky Hatton channel his inner British warrior and get absolutely drilled in two rounds by Manny Pacquiao,
Even Paris Hilton seems disappointed Shane Mosley decided to run around the ring instead of engage Manny Pacquiao in their 2011 showdown.
Actor Mark Wahlberg must be wondering why the referee even allowed Miguel Cotto to continue after the beating he's taken from Manny Pacquiao so far in the fight.
Miguel Cotto allows Jeremy Piven to speak
"Excuse me, I'mma let you finish, Cotto, but Manny Pacquiao is one of the greatest fighters of all-time," I imagine Jeremy Piven saying during the Miguel Cotto vs. Manny Pacquiao promotion of the fight.
Floyd Mayweather with Triple H
WWE wrestling superstar and legend Triple H has been a big Floyd Mayweather fan for some time and can often be seen accompanying Mayweather to the ring and during post-fight interviews.
U.S. politician John McCain is such a big fan of boxing that he headed a push to pardon legendary Jack Johnson's dubious charges of transporting a white woman across state lines for immoral purposes.
McCain has yet to be successful in his goal so far, but he plans to continue the good fight.
While attending Mayweather-Mosley, Will Smith relates to being in the ring due to his vigorous training to become a chiseled athlete in the film Ali, a biopic about Muhammad Ali.
Nelson Mandela enjoying Laila Ali vs. Gwendolyn O'Neil at Kempton Park
Nelson Mandela, the former South African president and revolutionary, loves boxing.
He absolutely loves the sport and always backs his fighters to win, even if they have no chance.
singers Ray J and the late Whitney Houston attend Bernard Hopkins vs. Joe Calzaghe
The late Whitney Houston was a definite boxing fan.
The stars come out for Mayweather and Pacquiao, but to come out to a Bernard Hopkins fight, you really have to understand and love the sport.
Hip Hop musician Tupac Shakur was a boxing fan, but he was definitely a Mike Tyson fan most of all.
Shakur would often mention Tyson in his lyrics and reference him in interviews.
On the night Shakur was fatally wounded in a drive-by shooting, he had attended the Tyson-Seldon fight.
Arnold Schwarzenegger at Mayweather-Marquez
Action movie star and former California governor Arnold Schwarzenegger has been spotted at numerous big fights such as Margarito-Mosley, Mayweather-Mosley and Mayweather-Marquez.
So the next time there's a big fight, I'm sure he'll be back.
Film actor and director Sylvester Stallone bet everything on Rocky, his passion project film.
The film would win Oscars and go on to be one of the most popular films of all time.
Rocky is such a popular film, the titular character was inducted into the Boxing Hall of Fame in 2011.
It takes a true boxing fan to construct such an iconic boxing figure.
Mark Cuban holding up one of Mayweather's world titles
Businessman Mark Cuban loved his Dallas Mavericks, but he also loves the sport of pugilism.
Cuban can be seen at Mayweather-Hatton and many other major events in the sport of boxing.
Angelina Jolie and Brad Pitt
The acting couple of Angelina Jolie and Brad Pitt are not just two of America's biggest stars, but also two of America's biggest lovers of the art of pugilism.
Spotted here at Mayweather-Hatton, they love a good scrap.
50 Cent and Floyd Mayweather
Rapper 50 Cent was originally a junior Olympian boxer before moving into the world of narcotic sales and eventually a rap career.
His love of the sweet science made him and Floyd Mayweather instant best buds.
The two have been inseparable for years.
50 Cent's presence has become a mainstay of the Mayweather training camp.
Muhammad Ali attends every big and even little fight possible.
Other former boxing legends can be spotted from time to time, such as Sugar Ray Leonard or Mike Tyson, but not as consistently as Ali.
Ali gave the world one of the best careers in boxing history and now wants to see where the next generations will take it long after he is gone.
Will he find the one that makes him smile and know the sport he helped bring attention to for decades is in good hands?
That's hard to say, but Ali will be there in the crowd, watching and anticipating as all fans do.