The Post Malone concert scheduled for Saturday night at TD Garden has been postponed "due to unforeseen circumstances," the Boston entertainment venue said.
The rapper posted a statement to his Twitter account confirming the news and apologizing to his fans.
Post said he felt "so good" when he performed for a packed TD Garden crowd Friday night, but then he woke up Saturday with cracking sounds on the right side of his body. He went on to say he was having a very difficult time breathing and felt a "stabbing pain" whenever he moved.
Post added that he was at a hospital and could not do his second show that was planned for Saturday night due to the pain he's experiencing.
The concert had been set for 7 p.m., and the news that it had been postponed appeared to come late from both the Garden and the rapper. The venue made the announcement with a 7:19 p.m. Twitter post, while the rapper posted his statement to Twitter around the same time.
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The TD Garden said fans should hold onto their tickets that can be used for a new date once it has been announced. There was no immediate word on when that might be.
The rapper apologized several times in his statement, saying he felt terrible for postponing his second Twelve Carat Tour stop in Boston.
"I love y'all so much. I feel terrible, but I promise I'm going to make this up to you. I love you Boston, I'll see you soon. I'm so sorry," he wrote.
The 27-year-old has been on the mend after bruising his ribs in a nasty fall during a Sept. 17 concert at the Enterprise Center in St. Louis. While performing, Post fell against a hole on stage, hitting his chest. That show was paused while he was examined by medics, but he went on to perform five more songs.
The day after, he spoke about the incident in a selfie video on Twitter, saying he was back from the hospital and everything was "good," specifically noting he had been given some pain medicine and would be able to continue his tour.
His manager, Dre London, also took to Instagram to refute rumors that the rapper had broken three ribs. London said x-rays revealed Post had only bruised his ribs.
Fans who spoke to NBC10 Boston outside TD Garden Saturday night had come from Connecticut, New Hampshire, North Carolina and even Florida. Some said they had been waiting months for Saturday's concert. It was even a surprise for one fan -- but the real surprise came when they all showed up to the concert, only to be turned away.
Fans were feeling all the emotions after they learned Post's concert had been postponed.
"I cried a little… I was very upset," one woman said.
"Post, I’m angry. I had to get a babysitter to watch both of my kids. My wife is over there too, you know what I mean and you canceled so now…I don’t even know what to do," another man said.
Fans were also sympathetic towards the rapper.
"I came all the way from Florida two nights in a row. I was here last night and I’m back again. I’m the biggest fan, probably the oldest. I love you Posty. I hope you are okay," one concertgoer said.
"I’m very disappointed but I hope that he’s feeling better for the next time he comes," one woman quipped, adding with a laugh that she's mad.
The fan who was surprised with the concert tickets -- only to find out it had been postponed -- said he truly felt bad for the person who orchestrated the whole thing.
"It's messed up," she added.
"I hope Posty’s alright," another fan shared, saying he had at least bought a t-shirt that he'll use for the next show.
Post's next concert is scheduled for Tuesday in Cleveland. There's no word yet if any of his other shows will be canceled.