Sources close to the situation told NBC News on Wednesday that the US president’s closest aides and campaign team woke-up feeling "worried," "quiet" and "in shock," following Tuesday night’s televised debate with Mr Biden.
The 90-minute debate was widely condemned as being among the worst in living memory, with moments of chaos and disorder that were topped by the president’s refusal to denounce white supremacy.
One CNN commentator, Jack Tapper, appeared to speak for many Americans when he described Tuesday’s spectacle as “a hot mess inside a dumpster fire inside a train wreck”, and “the worst debate I have ever seen”.
With Mr Trump continuing to trail the Democratic presidential nominee in state and national polls, some advisers were said to be concerned that Tuesday wasted an opportunity to appeal to any undecided voters.
“Trump lost one of the remaining opportunities he had to reshape the election and not walk into election day as the underdog," a former White House official told NBC.
They added: "but he walked into election day last time an underdog and won, so maybe he doesn't need to reshape the election".
The president claimed on Wednesday to have “won” the debate, telling reporters that "We won the debate by almost every poll I saw,”
“If you look at the various polls. I looked at six of them. We won every one of them," he added, without clarifying which polls he had seen.
One CBS News poll had 48 per cent of viewers saying Mr Biden had won the debate, with 41 per cent saying the same for Mr Trump.
Another poll conducted by CNN said 60 per cent of viewers thought Mr Biden had come out on top on Tuesday night, whilst 28 per cent said the same for Mr Trump.
In an announcement on Wednesday, the United States presidential debate commission said changes would be made to two up-coming televised debates to ensure moderators can keep control, following Tuesday's fiasco.