The first presidential debate on Tuesday devolved into name-calling, yelling and hurling personal insults as President Donald Trump derailed the discussion with constant interruptions, unfettered by moderator Chris Wallace, who struggled to maintain order.

Determined to rattle his opponent, Trump spent most of the first 20 minutes of his debate with former Vice President Joe Biden attacking him and constantly interrupting his Democratic rival in a sequence that ended with Biden asking him to "shut up."

'He Doesn't Want to Answer the Question'

US Presidential debate 2020,
Donald Trump (left) and Joe Biden at the presidential debate on Tuesday. Twitter

The moment came during a chaotic segment between Trump and Biden, who kept talking over each other as Wallace tried unsuccessfully to keep them in line.

During the first portion of the debate on the topic of the Supreme Court, Wallace asked Biden if he was willing to tell the American people whether he would support adding justices to the bench if Trump's conservative pick Amy Coney Barrett is confirmed to replace liberal icon Ruth Bader Ginsburg.

Biden said he would not take a position on the issue and instead urged people to go out and vote. "Whatever position I take on that, that'll become the issue. The issue is the American people should speak. You should go out and vote. You're in voting, now vote and let your senators know how strongly you feel. But vote now," Biden said.

As Biden was talking, Trump repeatedly asked him, "Are you going to pack the court?"

"He doesn't want to answer the question," he added.

'Will You Shut Up Man?'

"I'm not going to answer the question, because the question is, the question is, the question is...." Biden said, as Trump continued to press him to answer. "Why won't he answer the question?" Trump said as Biden tried to speak.

Unable to answer due to Trump's constant interruption, Biden then shut his eyes and said, "Would you shut up man?"

"This is so unpresidential," Biden scoffed before following it up with, "Keep yapping man!"

"The people understand, Joe. In 47 years, you've done nothing. They understand," Trump said, after which Wallace ended the segment. Watch the clip below: