Cleveland Cavaliers

Madness in Cleveland.

Thousands of Cavs fans have packed the I-X Center next to the airport in Cleveland ... waiting to greet LeBron and company the second the champs step off the team jet!

The scene is crazy ... people decked out in Cavs gear, holding signs, chanting -- and the traffic to get anywhere close to the action is reportedly insane.

The Cavs plane is supposed to land around 12:30 PM ET -- and it should an epic welcoming party.

Stay tuned ...

Charles Oakley was PISSSSED while waiting outside of the Cleveland Cavs locker room after Game 7 Sunday night -- at one point telling security, "Touch me, see what happens."

The 52-year-old NBA great is a Cavs fan -- he's from Cleveland -- and we're guessing he was waiting around to celebrate with the team.

But something went awry -- as captured on video by USA Today's Sam Amick -- and it culminated in Oakley essentially challenging security to step up ... or shut up.

Rihanna ... talkin' trash!!

Didn't take RiRi long to go in on Steph Curry after Game 7 -- throwin' a little shade at the NBA's regular season MVP on Instagram.

Rihanna's a HUUUGE LeBron James fan -- and overloaded her social media with tributes to King James after the Cavs took the title ... even calling him "Bae" at one point.

It's good to be the champ.

The Cavaliersmade a pit stop on their way back to Cleveland -- landing the team jet in VEGAS for a wild Sin City championship celebration ... complete with insane champagne showers!

LeBron, J.R. Smith, Kyrie Irving and the rest of the squad rolled into XS nightclub at the Wynn -- and were greeted like they just won the Larry O'Brien trophy ... 'cause they did!

J.R. Smith even took his shirt off at one point ... because ... well, why the hell not?

Congrats!

There was a report that crazy fans in Cleveland stole a fire truck in the wake of the Cavs championship victory.

The Cleveland PD shot down the report ... kinda.

Stay safe out there.

Didn't take long for President Obama to weigh in on the NBA Finals -- with POTUS taking to Twitter to dap up LeBron and the Cavs for shocking the Warriors in Game 7.

"What a game and what a series for the @Cavs," Obama tweeted roughly an hour after the game ... "Happy to see @KingJames bring it home for Cleveland!"

LeBron reacted to the tweet live on NBA TV.

As if the Cavs needed another reason to clinch Game 7 ... a Cleveland bar is offering LeBron and co. FREE FOOD FOR LIFE if they bring home the title this Sunday!!

Red Bar and Lounge -- about a 20 minute drive from Quicken Loans Arena -- is pumped about the potential victory and said, if they win, they will hook up every single player on the roster with free grub for life.

One of Red Bar's owners, Maha Metri, tells TMZ Sports, "Cleveland has been waiting for over 50 years for a championship. With one game away LeBron and the team can make the city's dream come true."

Mark Cuban might've just gotten his northern California privileges revoked for good ... 'cause the Mavs boss just publicly proclaimed he's throwing his support behind the Cavs in the NBA finals.

Justin Bieber got into an all-out street brawl with a guy much bigger than him Wednesday night in Cleveland.

TMZ obtained this video of Bieber, shot shortly after 11 PM, outside his hotel in downtown Cleveland -- he was face-to-face with the guy, who threw a light blow at Justin's head. That's when Justin uncorked a blow right to his face ... and then it's on!

Several people were standing nearby and tried to jump in, but the fight ends up spilling to the ground.

It's unclear what started the scrap. Bieber was in town for the game 3 of the NBA Finals, and was wearing a Cleveland Cavaliers shirt ... so it could be post-game trash talk. Also, witnesses say Bieber was getting peppered with requests for photos, and we know how he feels about that.

Overall ... we'd say Justin held his own, though he ended up on the bottom of the pile.

This is a cool shot ...

Kareem Abdul-Jabbar personally greeting LeBron James as he jogged through the tunnel after Thursday night's playoff blowout ... and LeBron was all smiles.

KAJ was on hand at Quicken Loans Arena as the Cavs stomped all over the Raptors to take Game 2 over the Eastern Conference Finals. He's clearly a fan of the team.

It's even more interesting considering the Cavs have won 10 straight playoff games -- 1 game shy of passing Kareem's '88-'89 Lakers, which won 11.

The record is 12 straight playoff wins -- set by the '98-'99 Spurs.

The Cleveland Cavs just extended a VIP invitation to the new UFC heavyweight champ Stipe Miocic -- an Ohio native who shouted out the NBA team after winning the belt at UFC 198 this past weekend.

TMZ Sports spoke with the Cavs who told us ... they saw the video of Stipe encouraging the Cavs to follow his lead and win the championship -- and they LOVED IT!

In fact, we're told the team reached out and invited him as their guest for Game 1 of the Eastern Conference Finals Tuesday night at the Quicken Loans Arena.

Miocic accepted -- obviously -- and we're told the team plans to honor him tonight for making Cleveland proud.

Congrats, champ!

Cleveland can stop holding its collective breath ... the LeBron vs. Bieber crisis is officially over ... and somehow, they both emerged victorious.

As we previously reported, Justin's "Purpose" world tour was scheduled to touch down at the Quicken Loans Arena in Cleveland on April 26th ... the same night as Game 5 in the Cavs vs. Pistons series.

The two sides were scrambling to work out a plan -- (with the Bieber concert likely to get bumped to a later date) -- but to everyone's surprise, the Cavs SWEPT the Pistons in 4 games!!!

Translation -- the concert will go on as planned and everyone is happy!!

Get nervous, Cleveland ... 'cause if LeBron James is testing the waters about a return to Miami, Gabrielle Union says her husband's team would "welcome him back with open arms."

We got Mrs. Dwyane Wade out in Beverly Hills and had to ask her thoughts on a possible reunion of the Big 3 ... mostly due to the rumors LeBron is already fed up with the Cavs.

Gabby's definitely into the idea ... and why not? Bron and Wade did win 2 championships together.

Plus, LBJ and D-Wade are super BFFs ... they even worked out together in Miami in the middle of the NBA season ... rubbing some CLE people the wrong way.

2 huge stars ... 1 arena ... both are booked on the same day -- and now everyone wants to know who's gonna get bumped in Cleveland, Justin Bieber or LeBron James??!?!

LeBron James will take his talents out of Cleveland -- and play for another team -- before his career is over ... so says NBA legend Kenny Smith.

The "Inside the NBA" star was out in L.A. -- when we asked about all the King James drama that's been going on this past week ... including the infamous Cavs unfollow on Twitter.

"That's disrespectful," Smith said ... "That's like unfollowing your kids."

Ya gotta watch the clip ... Smith is pretty strong about why he thinks Bron will leave The Land.

Question is ... where does he go next?