Cleveland Cavaliers

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Johnny Manziel went on a cursing rant on an NBA referee during LeBron James' homecoming game in Cleveland last night ... and his rage was captured on video.

Johnny Football was pissed off after what he clearly felt was a BAD call, and repeatedly yelled -- from his courtside seat -- "Bulls**t" and "F**k" ... for a solid minute.

LeBron James stunk up the basketball court for his huge homecoming game -- but still pulled out a huge victory for business owners in downtown Cleveland ... TMZ Sports has learned.

We spoke with several restaurants, bars and pubs near LBJ and the Cavs' home arena -- and they tell us revenue was up a whopping 80% on average ... from the Lebron-less home opener last year.

The Cavs pulled out all the stops for the King's return -- Imagine Dragons and Kendrick performed -- and it paid off. One biz owner told us they attracted tons of people from the 'burbs who normally wouldn't be there.

In fact, we're told many fans spending money downtown didn't even go to the game ... because cash registers were ringing before, after, and DURING the Cavs' loss to the Knicks.

The Cleveland Cavaliers tell TMZ Sports ... they have NO IDEA why a ball boy was serving players Gatorade masked in a Powerade bottle last night -- but they're gunning to find out why.

Twitter EXPLODED last night during the Knicks-Cavaliers game when a TV camera caught a Cavs ball boy making the switch behind the Knicks bench.

Now the Cavs -- who have a sponsorship deal with Gatorade -- tell us they're investigating why their official drink was poured into a competitor's bottle.

"We are looking into why the Powerade bottles were used. We're trying to figure out what happened."

The team made sure to clarify that the incident did not occur on their bench -- however. it was a Cavs employee who made the switch.

So what the hell happened? "That's what we're trying to figure out."

LeBron James was welcomed back to Cleveland last night by a huge band of celebs -- including Justin Bieber, Michael Strahan and even Johnny Manziel.

The Cavs lost in Bron's first game back with his hometown team -- but there was one guy in the stands who was happy about the upset ... Spike Lee ... notorious Knicks fan who traveled to Ohio to support his team.

Also in the stands ... Kendrick Lamar, David Beckham, Joe Haden and Kevin Hart.

The King of the NBA now has a Princess in his realm ... with LeBron James welcoming his first baby girl to the world.

The 4-time NBA Most Valuable Player and his wife Savannah welcomed their 3rd child last week at a hospital in their hometown of Akron, Ohio.

Zhuri James is not the heir to the NBA throne ... LeBron already has 2 boys ... but something tells us WNBA officials are already looking 21 years down the line.

The couple announced the name back in August while on vacation in Greece.

Mazel tov!

WNBA superstar Britney Griner has a message for the Ohio man begging to be released from jail so he can watch LeBron James play next year ... dude, get a TV.

The All-Star center was at LAX when TMZ Sports asked her about Jason Goudlock, an Ohio prisoner who made headlines for asking for parole from his 20-year sentence ... so he could watch the Cavs.

Peep the clip -- anyone expecting some sympathy from the 6'8" ball swatter will be sorely disappointed.

The 16,768 sq ft pad is just plain sick ... 6 bedrooms, an infinity pool, wine cellar and dockage space that can accommodate two 60 foot yachts.

Good news for LeBron James' rap career -- it could be getting some help from Drake ... 'cause the hip hop superstar tells TMZ Sports he's down to collaborate with The King.

Drake was leaving the L.A. premiere of LeBron's new TV show "Survivor's Remorse" (Bron's one of the producers) ... when we asked if he'd ever team up with James, who recently released his very first rap single.

Drizzy didn't exactly say "no" ... and seemed pretty open to bringing James onto a track.

BTW -- it seems LeBron is really taking this Hollywood thing seriously ... the guy rocked a TURTLENECK under his suit Tuesday night ... despite the fact it was 70 DEGREES IN L.A.!!!

Work hard, play hard ... that's the way it was for LeBron James and Chris Paul Sunday -- who hit the gym together during the day and the CLUB together at night.

LeBron and CP3 spent their Sunday training at the gym at UCLA with Bron's Cleveland Cavs teammate Tristan Thompson ... and even posted a pic to Instagram.

But when the sun went down, Bron and Paul freshened up -- and hit up Greystone Manor in West Hollywood.

The two arrived around midnight and spent about 2 hours in the place ... finally leaving the when the club shut down.

The two have been good friends for years -- but the big question, when the tab came ... who paid?

LeBron James hit the L.A. club scene last night -- rollin' into Hooray Henry's in West Hollywood with one of his boys ... and a sick $50k watch on his wrist.

The NBA superstar didn't say much on the way out of the place ... but if you wanna see what a guy who reportedly made $72 million last year rocks out to the nightclub check out the clip.

Snapback -- check.

Wedding ring -- check

$50k custom Audemars Piguet watch -- check.

It's good to be rich.

LeBron James is RETURNING TO CLEVELAND ... telling Sports Illustrated he has finally made up his mind to leave the Miami Heat.

Bron is from Cleveland ... and still has a house in Akron.

During his 4-year run with the Heat, LeBron won 2 NBA championships and made the NBA Finals all 4 years.

James wrote an essay for Sports Illustrated explaining his decision ... in which he writes, "I always believed that I’d return to Cleveland and finish my career there. I just didn’t know when."

"After the season, free agency wasn’t even a thought. But I have two boys and my wife, Savannah, is pregnant with a girl. I started thinking about what it would be like to raise my family in my hometown. I looked at other teams, but I wasn’t going to leave Miami for anywhere except Cleveland. The more time passed, the more it felt right. This is what makes me happy."

James says, "I'm not promising a championship" ... but says that's clearly his goal ... a goal that will take several years to accomplish.

Cleveland Browns QB Johnny Manziel just tweeted -- "YESSSSSSSS!! Couldn't be happier for my guy @KingJames and the @cavs #Cleveland."

Question: How do you fix the hapless Cleveland Cavaliers?
Answer: Porn star gang bang.

At least, that's the solution hardcore adult actress Ava Devine offered up in NYC the other day ... in fact, she's such a big Cavs fan, she's willing to take one (or 5) for the team.

"If [the Cav's] make the playoffs ... I will bang them all and bring a girlfriend," Devine said.

She also wanted us to know, "I can handle them all by myself."

Canadian native Anthony Bennett -- the first Canadian EVER to get picked first in the NBA draft -- has just received an even greater honor ... THE KEY TO HIS CANADIAN HOMETOWN!!!

The mayor of Brampton in Ontario released a statement today, saying she presented Bennett -- who was drafted by the Cleveland Cavaliers last week -- with the key on Canada Day yesterday ... in honor of his incredible non-hockey achievements.

For our Canadian readers: basketball is a game in which two teams vie to shoot a ball through their opponent's hoop. No actual baskets are involved, and players tend to retain most of their teeth.

The mayor added, “All of Brampton wishes Anthony the very best with the Cleveland Cavaliers and we look forward to cheering him on during the NBA season.”

That is, as soon as they figure out what the NBA actually is ... and no, the Raptors don't count.

Take it away, Kyle's mom!

Obviously, Cuban is referring to the fact that James decided to amp up the drama ... and screw with practically everyone's emotions ... before announcing on live TV last night that he was ditching the city that loved him to try and win a quick championship with a "super team" in Miami.