Boxing's Golden Boy Oscar gets punchy with the Dancing with the Stars Golden Boy


Apparently, sparring with Mario Lopez doesn’t win fights for Oscar De La Hoya.

Several days prior to his major match-up Saturday in Las Vegas against “Pretty Boy” Floyd Mayweather – which resulted in De La Hoya’s losing in a split decision – Golden Boy Oscar held a friendly boxing round with Lopez, a Golden Boy himself, having recently been named one of People en Espanol‘s Most Beautiful of 2007.

“It’s like shooting hoops with Kobe Bryant,” Lopez, 33, tells PEOPLE of being in the ring with De La Hoya. “You know you’re going to lose, but it’s fun anyway.”

Clearly, there was one main show in town Saturday night, causing celebrities to turn out with both fists raised.

On hand at the MGM Grand Las Vegas for the big bout, in addition to Lopez: Tobey Maguire, Jay-Z, Leonardo DiCaprio, Matthew McConaughey, Charlie Sheen, Eddie Murphy, Helen Mirren, Denzel Washington, Jack Nicholson, Eva Longoria, Jeremy Piven, Kevin Connolly, Michael Jordan, Michael J. Fox, Diddy, Sacha Baron Cohen, Will Ferrell and Jermaine Dupri, as well as couples Jennifer Lopez and Marc Anthony, and Jim Carrey and Jenny McCarthy.

One person who was very happy with Mayweather’s victory: 50 Cent. The hip-hop star bet $1 million on the winner and walked out of the arena saying “easy money”.

After the fight, hip-hop royalty was on display at the Venetian’s Tao Nightclub. Hanging in the VIP booth: Jay-Z, Usher, Diddy, 50 Cent, Jermaine Dupri, Young Jeezy, Nelly and Ashanti. Baron Cohen showed up later, but kept a hat low over his eyes.

“There’s been a lot of negativity given to hip hop lately, but I want you to look at this group,” Diddy said. “There is nothing but love up here.”