Rick Gates, Manafort's long-time deputy, came in for a withering cross-examination as he took the stand in a packed federal courtroom in Alexandria, Virginia.
Both Manafort and Gates were indicted past year on charges of bank and tax fraud as part of Special Counsel Robert Mueller's probe.
Four employees at Dr. K's firm established and named the entities - Leviathan Ltd. and Peranova Ltd. are two of the more high-profile examples - where Manafort and Gates held millions of dollars of payments to Manafort's Davis Manafort Partners (DMP) and DMP International from their overseas political clients.
From 9:30 am until just after 3 pm, Gates corroborated the testimony of Manafort's bookkeeper and two accountants from the days before, along with prosecutors' evidence. He's expected to go for at least another hour in questioning with Manafort's attorney's.
Gates embezzled hundreds of thousands of dollars from Manafort by filing exaggerated - and at times, completely fabricated - expense reports, Downing forced him to admit Tuesday.
In testimony Tuesday, Gates laid responsibility squarely at Manafort's feet for a series of crimes, as he described to jurors how he repeatedly submitted fake financial documents at Manafort's behest as his former boss became concerned he was paying too much in taxes and, later, that his funds were drying up.
Prosecutors will likely draw Gates back to those facts and away from his own misbehavior on redirect examination.
Gates answered: "I don't recall". The special counsel's office has pushed back against the leak allegation, and while an Federal Bureau of Investigation agent testified he was present at a meeting with AP reporters about Manafort, the agent said the AP was offered little more than a "no comment" and an acknowledgement that their reporters were generally on track.
Manafort to Gates in 2011, telling him to "proceed" with secret foreign wire transfers.
She said even though she worked with Gates a lot, it was clear to her that Manafort "knew what was going on" in most instances.More news: Stokes arrives at court to face affray trial
Asked why he had lied, Gates said he had done so at Mr Manafort's request. "I'm not very patient, so don't try my patience", Ellis said.
He also made clear he was testifying against Mr Manafort in the hopes of receiving a lesser prison sentence, having pleaded guilty as part of a deal with special counsel Robert Mueller.
Manafort, a longtime Republican political consultant, has pleaded not guilty to 18 counts of bank fraud, tax fraud and failing to disclose foreign bank accounts.
As well as being a senior aide on Trump's election campaign, Gates served as the deputy chairman of the USA president's inaugural committee. She also said Manafort told Banc of California that his company made almost $4.5 million when the actual amount was $400,000.
Michael Zeldin, a former federal prosecutor, said that in Downing's remaining hour of cross-examination on Wednesday, he needs to keep painting Gates as an unreliable person who can not be trusted.
Under questioning by prosecutor Greg Andres, Gates walked the six-man, six-woman jury through the foreign bank accounts used by Manafort to receive payments from Ukrainian politicians - money that was not reported to the Internal Revenue Service (IRS).
The email from Manafort came after Gates informed him that the tax accountants had calculated that Manafort would have an increase in taxes of about $509,000 in 2014.
Downing outlined how Gates gave false and misleading information to the special counsel after he had entered his plea agreement. But Trump has shown interest in the proceedings, tweeting support for Manafort.
And Gates faced fraud charges from the special counsel after it discovered he had written a letter to a Swiss movie production company falsely claiming that his own production company was investing in a film project by his friend, Steve Brown.
Manafort and Gates were the first two people indicted in Mueller's investigation into potential ties between Russian Federation and the Trump campaign.