WorldCom's ex-boss Bernie Ebbers ordered adjustments to the firm's books, the telecoms firm's ex-financial chief has told a Manhattan court.
Scott Sullivan says his boss knew what was going on
Scott Sullivan is the prosecution's key witness against Mr Ebbers, who has denied charges of fraud and conspiracy in relation to WorldCom's collapse.
In his second day of testimony, Mr Sullivan said his ex-boss repeatedly told him: "We have to hit our numbers".
WorldCom's accounting scandal was the biggest in US corporate history.
The telecoms company went into bankruptcy with an $11bn (£5.9bn) hole in its books after the scandal came to light in 2002.
Mr Sullivan, 42, pleaded guilty to fraud last year for his role in massaging WorldCom's books and agreed to assist prosecutors in their case against Mr Ebbers.
He told the court that Mr Ebbers knew of the company's problems with falling revenues and high expenses.
Mr Ebbers allegedly wanted his finance director to ensure that WorldCom's earnings lived up to the expectations of US stock market analysts, and of shareholders, who often took their cue from telecoms industry analysts
Mr Sullivan said he had warned his boss in late 2000, two years before WorldCom's problems came to light, that revenue figures would need adjusting if they were not to fall short of analysts' expectations.
"I told Bernie, this isn't right. We're doing this, we're making this change, we're making this adjustment because this is the only way I can get the numbers up to the expectations of the market place," Mr Sullivan testified.
He said that Mr Ebbers took the paperwork, "studied it awhile and looked down and said, 'We have to hit our numbers'".
Mr Ebbers used the same words when told the firm's expenses threatened its ability to meet its earnings forecasts.
Mr Ebbers' lawyers claim that their client was unfamiliar with detailed accounting practices and left that side of the business to Mr Sullivan.
However, Mr Sullivan has testified that WorldCom's boss was a hands-on manager who paid great attention to detail.
Mr Ebbers could face a sentence of 85 years if convicted of all the charges he is facing.
WorldCom's problems appear to have begun with the collapse of the dotcom boom which cut its business from internet companies. Prosecutors allege that the company's top executives responded by orchestrating massive fraud over a two-year period.
WorldCom emerged from bankruptcy protection in 2004, and is now known as MCI.