TMZ.com

A scary moment for Carlos Santana and his fans, as the legendary musician collapsed onstage during one of his concerts.

Santana was performing at Pine Knob Music Theater, outside Detroit, Tuesday night, when a concertgoer tells us the medical emergency happened. We're told Santana was bout 4 or 5 songs into his set, and started to sing a song called "Joy."

Realizing something was wrong, we're told Santana sat down in front of the drums, and then collapsed backward. From there, many staffers, including EMTs rushed to his aid.

You can see in video from the show, a black tarp was brought out in order to shield Santana while officials were working on him.

Thankfully, Santana came back around, and was seen waving to the crowd as he was wheeled off the stage.

It's currently unclear what caused Carlos to collapse, but it appears he was taken to the hospital for further evaluation.

It looks like it's back to business for Travis Barker 'cause he's getting back into the studio ... after being released from the hospital.

Travis was spotted Tuesday behind the wheel of a Mercedes G Wagon, heading into a Calabasas studio to make some musical magic.

Clearly, the Blink-182 drummer is feeling a whole lot better and looked pretty healthy, sporting black shades and a "D.O.A." T-shirt as he emerged from his vehicle in the studio's parking lot.

Travis was anything but dead on arrival, though. In fact, he greeted the studio operator with an energetic fist bump, before heading inside.

We're told several other musicians arrived at the studio about 30 minutes later along with Travis' assistant, who went on a food and coffee run for the entire crew. Whatever Travis and Co. are cooking up from behind those walls must be good ... they've been rocking out for hours, we're told.

Of course, this comes after Travis was rushed to the hospital last week. TMZ broke the story ... he had a colonoscopy that triggered pancreatitis, which is a serious health issue that kept him in the hospital bed for days as he was being treated.

Travis told folks on social media, "During the endoscopy, I had a very small polyp removed right in a very sensitive area, usually handled by specialists, which unfortunately damaged a critical pancreatic drainage tube. This resulted in severe life threatening pancreatitis."

This isn't the first time we've seen Travis out since the health scare. Travis and Kourtney were also spotted taking a joyride in a vintage truck on July 4th, with Penelope and Reign cruising in the back.

Scoring anything Janis Joplin owned would be cool, but an instrument that belonged to Janis AND Jimi Hendrix is a whole new level of rock memorabilia.

We're talking about a hand-painted mandolin that fetched a whopping $281,250 after 29 bidders battled it out. The history on this item is pretty cool, so that price could be considered a steal.

Up until now, it has never been up for auction, and had been a part of a private collection for 20 years after it was acquired from the Memphis Music Hall of Fame.

More importantly, guitar god Jimi was the last famous owner ... having received it from Janis as a gift.

Besides just being a cool instrument to own, the mandolin represents the friendship between 2 of the most iconic rock stars of all time. It's painted with flowers and phrases such as "love thy neighbor," "Janis Joplin & B.B.H.Co," and "Jimi Hendrix."

The new owner got themselves 2 Rock and Roll Hall of Famers for the price of one.

BTW, the Johnny Depp motorcycle from "Cry-Baby" was a part of the same auction ... but its reserve price wasn't met. Instead, GWS auctions say it has several museums interested and currently vying for it.

Travis Barker has resurfaced after his scary hospitalization last week, and he didn't look the worse for wear.

Travis and his wife Kourtney Kardashian took a ride in a vintage orange truck on the 4th, with Penelope and Reign in the back.

They looked super chill, as they listened to Bruno Mars' "Grenade."

Travis has said he's feeling a lot better after landing in the hospital.

TMZ broke the story ... he had a colonoscopy which triggered pancreatitis -- a serious problem that kept him in a hospital bed for days as doctors ran tests and treated the ailment.

Travis took to social media last weekend and said "I went in for an endoscopy Monday feeling great. But After dinner, I developed excruciating pain and have been hospitalized ever since."

He went on ...  "During the endoscopy, I had a very small polyp removed right in a very sensitive area, usually handled by specialists, which unfortunately damaged a critical pancreatic drainage tube. This resulted in severe life threatening pancreatitis."

Katy Perry sent a message this holiday weekend to express frustration about the Roe v. Wade decision -- but all Twitter wants to do is point out what it sees as hypocrisy.

The singer tweeted Monday about the 4th of July and what it means in her eyes in the wake of the Supreme Court's ruling to reverse the landmark decision ... effectively outlawing abortions almost immediately in several states across the country, and more to come.

She sarcastically writes, "'Baby you’re a firework' is a 10 but women in the US have fewer rights than an actual sparkler smh" -- clearly referencing her 2010 track of the same name.

NBD, or so you would think ... rather than getting praised for her pro-choice sentiment here -- as many celebs have been lately -- Katy is actually getting dragged to no end right now. And it all has to do with who she publicly supported for L.A. Mayor ... aka, Rick Caruso.

As we reported ... KP was one of many celebs who endorsed the billionaire entrepreneur and real estate developer running for Mayor. And while he didn't outright win in June's election -- he has a chance to take it home in Nov. in a runoff race with Rep. Karen Bass.

The problem ... Caruso, who's running as a Dem, has been perceived as wish-washy on his abortion stance over the years, at least that's what old interviews from the 2000s suggest. Until recently ... Rick was a Republican and has donated to a lot of GOPers, including folks some say have it out for abortion rights -- all of which he's been called out over of late.

Now, he says he's pro-choice and touts himself as an advocate for women's rights. Unfortunately for him (and for Katy, it seems) ... Twitter's not buying it, and they're telling Katy to sit this one out due to her very vocal support for him.

She's far from the only celeb who backed Caruso, though -- Kim Kardashian also got behind him in the run-up to the election last month ... but she appears to have wisely dodged Twitter to lament the abortion sitch lately.

Harry Styles is devastated by the mass shooting in Copenhagen, where he was supposed to perform just hours later.

Harry canceled his concert Sunday ... after a gunman opened fire at Field's shopping centre, which is less than 2 football fields in distance away from the venue where Harry was supposed to perform later that night.

Harry said he was feeling utter "devastation" ... "I'm heartbroken along with the people of Copenhagen. I adore this city. The people are so warm and full of love."

He went on ... "I'm devastated for the victims, their families, and everyone hurting. I'm sorry we couldn't be together. Please look after each other. H."

Police say the shooter was a 22-year-old Danish man, and they believe he acted alone. Authorities have not ruled out terrorism.

The gunman entered the mall with a rifle and then began firing randomly at people inside the mall.

Sammy Hagar makes most of his money from booze, books and bars ... which he says is the precise reason he enjoys rocking out with his band. We will explain.

The Red Rocker joined us on "TMZ Live" and we asked if he made more money outside of music ... he does, and he tells us how his success in the business world benefits his art.

Sammy says the only reason he's still playing shows with his band, The Circle, is because he doesn't have to play music to pay the bills ... a big bonus for a 74-year-old rock star.

The former Van Halen frontman says whenever he plays a show nowadays, it's for fun and not about the paycheck. His wealth allows him to pay his band more, making everyone happy and giving him the feeling they're just like a good ol' garage band.

In addition to being in the Rock and Roll Hall of Fame, Sammy's a savvy businessman ... with legendary restaurants like the Cabo Wabo Cantina, where he sells his own lines of spirits. He also writes books, including his latest, "Sammy Hagar's Cocktail Hits: 85 Personal Favorites from the Red Rocker."

Janet Jackson was not impervious to technical difficulties that plagued Essence Festival -- losing audio midway through her performance ... but powering through to kill it regardless.

The singer was one of the big headliners at the NOLA concert series this weekend at Caesars Superdome ... where TONS of huge stars performed in an event comparable to Coachella. What was also comparable ... audio issues often experienced in a live show.

No exception for Janet, unfortunately, because during her set ... her mic seemed to cut out while she was in the middle of either talking or singing, seen here in video obtained by TMZ.

The good news is that this little hiccup appeared to go mostly unnoticed, and the rest of Janet's time on stage was a smash hit ... as she rifled through hit after hit after hit for more than an hour -- leaving fans more than satisfied with the tunes and choreography.

Now, it's worth mentioning ... there seemed to be quite a bit of sound issues throughout the past couple days of acts -- including some complaints about Halle and Chloe Bailey's set, with folks saying their levels were off and that they sounded funky to the live audience.

The audio for C/H were the least of some people's concerns though ... even more viewers at home were pissed that Hulu only live-streamed their very last song ... a recurring theme for the festival -- namely, who subscribers watching on Hulu actually got to see.

This was perhaps most notable during Friday's show, when Nicki Minaj was the headliner for the night ... even though her performance didn't end up making it onto the Hulu broadcast.

Angela Yee -- who was on hosting duties that night -- noted they weren't going to be able to show Nicki's set for audiences at home, citing "circumstances beyond our control." NM did indeed perform ... and she aired out her frustrations with whatever was going on BTS.

In light of Nicki's mishaps -- as well as other artists here and there -- many were daring Essence/Hulu to screw up Janet's set (jokingly), saying there'd be problems if they did.

Welp, they did end up screwing the pooch a little bit for JJ after all ... but no harm, no foul. She carried on like a pro, and appears to have put on a helluva number for everyone.

Adele says she was gutted by the criticism surrounding the cancelation of her Vegas residency, but still ... she has no regrets.

Adele, you'll recall, announced back in January, just a day before her residency was supposed to open, that she was postponing it. At the time she seemed to say the problems were COVID and production-related, but stories surfaced that folks on the production team said she was impossible to please.

Adele has now addressed it, telling the BBC, "I definitely felt everyone's disappointment and I was devastated and I was frightened about letting them down." She went on ... "I was a shell of a person for a couple of months. I just had to wait it out and just grieve it, I guess, just grieve the shows and get over the guilt, but it was brutal."

But, then she held her ground, saying, "I thought I could pull it together and make it work and I couldn't, and I stand by that decision. I'm not going to just do a show because I have to or because people are going to be let down or because we're going to lose loads of money. I'm like, the show's not good enough.”

She said she's working on rescheduling, but it seems there have been more problems ... there were reports she tried a different venue but that apparently didn't materialize.

Justin Bieber's grandmother was almost killed in a fiery car crash that she narrowly escaped, seemingly unscathed.

Word of the wreck was spread Saturday in a FB public community page specific to Stratford -- which highlights classic cars and expos in and around the Canadian region within Ontario ... where Bieber has family ties. A photo of the aftermath was posted, with what seems to be a page administrator asking if anyone in the community could ID who it belonged to.

A guy named Brandan Steven, who also appears to be related to Justin, came forward to claim he was in the accident depicted, and that Kathy Bieber -- JB's grandma on his dad Jeremy's side -- was the owner of the convertible, and that she too was inside.

Of course, folks on the page asked for more details about what exactly had happened here -- to which Brandan replied, "we were at a dead stop as a car was turning left a couple cars in front of us. Then a distracted driver rear ended us they say she had to be doing 70."

He goes on to say, "Wasn't good had to pull my grandmother out of car. could have been very bad if we were in there for even another 5 seconds as the doors were binded shut."

Within the comments of this post, people actually tagged Jeremy Bieber's FB page ... as well as Kathy herself, who has photos posing with the car. Of course, this is also the same Kathy with whom Justin has posed in the past ... specifically, when he was much younger.

There aren't a whole lot of public photos of him with Kathy and her husband, George ... who's Jeremy's biological father, but they exist and have been well-documented online. Kathy is Jeremy's stepmother, and thus ... Justin's step-grandmother.

Taylor Swift got an unwanted guest at her NYC building last month -- an alleged stalker who was just arrested by the NYPD after he threatened to do harm to the singer ... TMZ has learned.

New York law enforcement sources tell TMZ ... Joshua Christian was booked Friday night for stalking after police tracked him down at his home following several run-ins with Taylor and her security personnel.

Our sources say Christian showed up uninvited to Taylor's Manhattan home around 10:47 AM on June 12 with the "intent to annoy and harass" Swift.

We're told Christian buzzed up to Taylor's residence using the building's intercom. Our law enforcement sources say Christian allegedly threatened to hurt Taylor if she refused to be with him, but we're also told Taylor did not answer the intercom or call the police. We're told it was security who called the cops.

Adele performed at a huge concert in London Friday night, but the gig repeatedly came to a temporary screeching halt so she could help some fans.

She took the stage -- her first live concert in 5 years -- as the headliner at London's BST Hyde Park Festival. There were 65,000 fans screaming for her as she screamed back, "My God, I'm back at home!"

Adele said she was nervous but excited to be there.

Some fans waited for 7 hours in the heat to get in, so Adele sent them water.

Apparently, there were medical issues, because Adele stopped her show 4 times so a few of the fans could get help from EMTs and security.

The show lasted 2 hours and the crowd loved it.

Rihanna made her first official outing since becoming a mom, venturing out across the pond to support the new father and her partner, A$AP Rocky.

RiRi surfaced Friday at Wireless Fest in London, weaving her way through the crowd with her security detail as Rocky was performing on stage. She looks a little annoyed ... but that might have to do with the screaming fans surrounding her.

Rihanna was wearing a black puffy jacket, Cuban link chain, hoop earrings and black leggings.

She was spotted in L.A. getting on a private jet for the U.K. with baby in tow, so looks like the whole fam is there.

TMZ broke the story ... Rihanna and Rocky's little baby boy was born on May 13 in Los Angeles.

Remember ... Rihanna and A$AP announced her pregnancy back in January with a photo shoot in New York City, and RiRi proudly showed off her baby bump over the remainder of her pregnancy.

Aerosmith frontman Steven Tyler is out of rehab, after a successful stay, and those around him are excited about the progress he's made in a lifelong battle.

Sources close to Steven tell TMZ he checked out of a facility earlier this week, and actually stayed longer than the 30 days he was supposed to complete in order to make sure he felt good.

We're told the singer is totally clean and sober, doing "amazingly well" and looks good physically too -- our sources say he's at a healthy weight and his skin looks great.

As for the rest of his recovery, we're told Steven's realistic, he understands he's fighting a lifelong problem and recognizes his addiction ... so everyone's hopeful he'll stay clean and sober.

It was back in May when Aerosmith announced, "As many of you know, our beloved brother Steven has worked on his sobriety for many years. After foot surgery to prepare for the stage and the necessity of pain management during the process, he has recently relapsed and voluntarily entered a treatment program to concentrate on his health and recovery."

Alicia Keys' hubby, Swizz Beatz, certainly knows how to make his wife smile while she's working abroad ... all with the help of some serious ice.

Alicia was performing in Milan Tuesday when Swizz and their kids surprised her with the massive bling -- a piece made possible by Celeb Jeweler Elliot Eliantte.

We're told at about 150 cts, the Egyptian-themed necklace set Swizz back about $400K. The baguettes around the main piece are set in a brick formation like the Great Pyramids.

The pendant is designed after Nefertiti, the queen of the 18th Dynasty of Ancient Egypt, but with Alicia's face on it. Nefertiti stands for strength, power, and beauty, while the infinity links symbolize eternal life.

Bret Michaels is currently being treated in a Nashville hospital ... a medical emergency that occurred just before he was set to get on stage with Poison.

The band is part of a massive stadium tour with Def Leppard, Motley Crue and Joan Jett. Audience members claim members from Poison got on stage Thursday night and let the crowd know Bret had to go to the hospital for a bad reaction to medication.

As a result, the other band members announced they wouldn't be able to perform their set.

Obviously, some fans were upset, going to Twitter to express their disappointment. One fan wrote, "Came all the way from KC to watch poison. Bret Michaels was admitted to hospital. No poison in Nashville."

Unclear how long Michaels will be sidelined, the tour continues with a date Saturday in Florida and Sunday in Mississippi.

Get well soon!!!