Three-time heavyweight champion Muhammad Ali is in “very grave” condition, Los Angeles Times reporter Lance Pugmire tweeted Friday. The legendary boxer was hospitalized in Phoenix on Thursday with respiratory problems. At the time, his representative said he was in “fair” condition and expected a brief hospital stay.

But “The Greatest” apparently has taken a turn for the worse. “Can confirm from very strong source that it's ‘very, very grave’ for @MuhammadAli,” Pugmire wrote on his verified Twitter account. “Ali's family is at his bedside, and I'm told ‘it could be hours’ by official understandably sensitive to all involved.”

The day before, Ali’s ex-wife Veronica Porche confirmed that her daughters, Laila and Hana Yaseem, were en route to see their father. “My daughters have both flown there, and I will be hearing from them when they arrive at the hospital,” she told Radar Online on Thursday. “I can’t comment more than that, but I will say it is not so great. I’ll just say that much.” The actress, 60, didn’t have anything optimistic to say about Ali’s current condition, other than adding he's "a real hero.” 

Ali, 74, is in intensive care and feared to be “near the end,” an insider told the Mirror on Friday.

The former athlete was admitted to the hospital with a respiratory problem, which was complicated by his neurological disease. “Like in the ring, Ali is a fighter on the ward,” the source said. “Doctors are working to regulate his breathing, but it is being hampered by his Parkinson’s.”

His children are worried about his declining health. “Ali is everything to them, and they are worried his problems are worse than first feared,” the insider said. “His children are all extremely concerned and dropped everything to be with him. They fear the worst.”

Ali’s publicist hasn’t issued another statement since he originally said the former champion was hospitalized.

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