But within minutes, a "corrected" statement was issued that said the same thing, except for the line "and Paul Manafort will tell the truth."
Trump on Wednesday put that line back in to the White House's latest official view of Manafort's veracity, and its impact on the political and legal fate of the president.
"Paul Manafort was with me for a short period of time," Trump said of the veteran Republican operative, who ran Trump's presidential campaign for less than four months.
"He did a good job and I'm very happy with the job he did," Trump told reporters.
"And I will tell you this, I believe that he will tell the truth," the president said. "If he tells the truth, no problem."
"As long as he tells the truth, it's 100 percent," said Trump, who routinely calls Mueller's investigation a witch hunt, and has denied any wrongdoing by either his campaign or himself.
Manafort's lawyers did not immediately respond to a request for comment.
Manafort's guilty plea came on the eve of the scheduled start of jury selection in his second criminal trial on charges that related to his consulting work for a pro-Russia political patrty in Ukraine, as well as for trying to tamper with witnesses against him after he was released on bond. His work in Ukraine predated his role in the Trump campaign.
Manafort, who is being held in jail without bond as he cooperates with Mueller, is the latest person in Trump's orbit to have pleaded guilty to criminal charges.
Last month, the president's former personal lawyer, Michael Cohen, pleaded guilty to tax crimes and to breaking campaign finance law in connection with a $130,000 hush money payment he made to porn star Stormy Danielsshortly before the election.