Hot Vegas

Mariah Carey is unreal ... we got audio of her full dress rehearsal for her Vegas show which opens tonight, and she sounds as good as she did in 1990 when she hit #1 with "Vision of Love."

Mariah performed for more than an hour Monday night to a packed house at The Colosseum at Caesar's Palace, and you gotta hear it. She hits every high note and sounds flawless.

We got audio from someone in the audience ... filled with various people who work in Vegas-related businesses. We posted a minute-and-a-half and sampled 4 songs. Wait till you hear her hit the high notes in "Emotions."

As for the naysayers who claimed she wasn't rehearsing enough ... whatever she did was clearly enough.

Chris Brown's birthday celebration on the Vegas strip had bottles poppin', hot chicks dancing, and ... absolutely adorable little baby videos.

Yeah, Chris' 26th bday party at Drai's was way different from his others, because this one featured home vids of Royalty on a big screen -- and you've gotta see the look on Chris' face ... daddy's totally fallen for his baby girl.

The video is pretty wild for a few reasons -- Chris hands out Ace of Spades bottles to fans in the crowd ... Chris shows off his badass dance moves ... AND Chris spins and goes flying off the stage!

Breezy also got the champ to come out -- Floyd Mayweather Jr. showed up flashing a tiny bit of the more than $200 mil he earned at the office last weekend.

Hip-hop producer Mally Mall must be bored with love triangles -- the "Love & Hip Hop: Hollywood" star is breaking up with Nikki Mudarris again, but this time THREE other chicks are involved.

Mall and Nikki are known to be on-again/off-again (a recurring theme from Season 1) and their relationship status was set to OFF after a blowup over a Las Vegas fight weekend party.

According to our sources, the couple was supposed to host a Mayweather/Pacquiao party at a rented house in town, but Mally showed up with three chicks that weren't Nikki ... and she didn't show up at all.

Season 2 is just writing itself.

Tyson Beckford's Chippendales debut was a real banger for Sheryl Underwood from “The Talk.”

She got an up close and semi-private viewing of Tyson's junk during the show -- prompting some odd comments in our newsroom about ... proper reactions to a wiener in your face.

In the blink of an eye, Chris Brown is no longer wanted for battery.

Law enforcement sources tell TMZ ... the guy who accused Brown of punching him early Monday morning during a basketball game in Vegas called the cops on Tuesday and told them he wanted to drop the case. He did not explain why.

At that point it was a no-brainer ... cops closed the case.

If ya wanna know what Tyson Beckford's junk looks like -- ask Sheryl Underwood … because "The Talk" host got an eyeful of his manhood in Vegas this weekend.

Beckford made his Chippendales debut Friday night at the Rio -- and gave Sheryl a very up close and personal introduction to his man parts ... while slipping out of his towel and into briefs.

Watch the vid ... Sheryl might have gotten the "biggest" show, but the audience got something too.

Stephen A. Smith is obviously a close personal friend of 50 Cent ... 'cause TMZ Sports has video of the ESPN host taking the stage with Fiddy this past weekend in Vegas and ... it's funny in a good way.

50 was performing at Drai's Friday night when 47-year-old Smith hopped onstage for what we'd like to believe was an audition for membership in the G-Unit.

Check out the clip -- Stephen A. seems to have mastered "what the hell am I doing up here" swag ... 'cause 50 doesn't seem bothered with him being in the crew ... even though he looks like someone's uncle.

Ludacris hosted a pool party at the Hard Rock in Vegas where an all out brawl broke out. Fists, furniture, bottles ... everything was flying!

Absolute mayhem, and at least twice as entertaining as the Pacquiao-Mayweather fight.

Chris Brown is accused of brawling with another guy early Monday morning during a basketball game in Las Vegas -- and police have named him a suspect for battery.

The altercation went down at the Palms Casino Resort -- according to police ... Chris was playing hoops at 3:42 AM and at some point he got into an argument with one of the guys playing -- and allegedly punched him. The pickup game was being played in the famous Hardwood Suite ... where Chris was staying.

Police responded to the scene, but didn't talk to Brown when they got there.

Cops say Chris now has 2 options: either sign a citation for misdemeanor battery, and agree to show up in court to face the charge -- OR take his chances with the D.A ... who would decide whether to press charges.

TMZ broke the story ... Brown just settled a lawsuit over another fight during a pickup basketball game in an L.A. gym.

But he also dodged a major bullet -- if the Vegas fight had happened before Chris got off probation in the Rihanna case -- back in March -- he could be going back to jail.

Here's footage of boxing superstar Adrien Broner GOING ABSOLUTELY BERSERK after winning at the baccarat table in Vegas Sunday night ... yelling, screaming and AIR HUMPING the table.

It's unclear how much cash Broner had on the table in the high roller's room at the MGM Grand -- but it must have been A LOT ... because any normie woulda been kicked out of the place in a heartbeat.

The video is pretty hilarious ... Broner starts yelling about how he "f**ked this town up" with "no condoms" ... while thrusting his junk into the table.

Congrats.

BTW -- Broner's weekend was definitely eventful ... here's video of AB pounding a whole lotta tequila at a post-fight party.

At least ONE Mayweather went down this weekend ... Floyd's father ... who ate it HARD during a pre-fight concert ... and TMZ Sports has the video.

Floyd Mayweather Sr. got up onstage and did his best James Brown impression to the tune of "Sex Machine" at the Fiesta Rancho Casino in Las Vegas on Thursday.

But while he was lettin' loose -- he lost his footing ... and went crashing down to the dance floor.

The good news -- like a true pro, the 62-year-old popped RIGHT BACK UP and continued to dance ... even busting out the signature James Brown "Camel Walk" dance move.

The REAL fight in Vegas went down the day after Mayweather-Pacquiao -- a huge melee at the Rehab pool party hosted by Ludacris.

The video is absolute INSANITY -- showing multiple brawls around the pool on Sunday at the Hard Rock Hotel -- fists, chairs, bottles, ice buckets and more were hurled. Even before the fight broke out ... you can see the crowd rip a door off its hinges to burst into the party!

Jamie Foxx and Will Smith's son Trey were also at the party at some point -- though it appears they weren't involved or injured in the fight. Perks of VIP.

Here's the odd thing -- Vegas cops tell us they got no calls for this brawl. We've got a call in to the Hard Rock too.

The Mayweather vs. Pacquiao fight was unanimous in everyone's eyes, but Manny's aunt and cousins are steadfast ... the fight was fixed.

Aunt Lilia and crew were leaving the Mandalay Bay on Sunday when our photog asked whether Manny was cheated, remember the boxer felt he had won the fight. His family went 5 steps further and claimed the whole thing was rigged and people got paid off.

They weren't done... they also trash talked Floyd.

TMZ Sports got Aunt Lilia back in March when she belted out the signature tune from 'Frozen." She might want to take some advice ... let it go.

Ass. Ass. Ass. Ass. Ass.

That seemed to be the theme at Dennis Rodman's birthday party blowout this weekend ... and TMZ Sports has all the thong'd out footage.

It all went down at Sapphire gentlemen's club in Vegas -- where The Worm was constantly flanked by a team of talented twerkaholic strippers.

But it wasn't just about lap dances ... Dennis also mingled with fans, signed autographs and took pics with anyone who asked.

Nobody was feeling Jay Z's after party in Las Vegas the way he was -- and that's a good thing ... 'cause from the looks of It Jay just wanted to be somewhere else.

Jay Z hosted, undoubtedly, the most exclusive Mayweather-Pacquiao bash at Marquee Nightclub Saturday night ... VIP tables went for $50k.

He and Beyoncé held court at their own table right on the dance floor -- but while the DJ was trying to get the crowd going, Jigga seemed to be dreaming ... of laying his head on his pillow.

Justin Bieber was amped up at Rehab in Vegas before the fight ... singing to Big Sean -- which is surprising -- and making his feelings about Manny Pacquiao clear.

Justin partied with the crowd before walking out with Floyd Mayweather, and at 33 seconds you can see him mouth the words, "f*** Pacquiao" ... he then flips the bird.

It's also interesting he's felling Big Sean, whose breaking with Ariana Grande did not go well. You'll recall he just gave her a squeeze from behind a few weeks back, which set Sean off. We're told Sean doesn't have hard feelings for Biebs ... he thinks Ariana just used him.