After more than a year of circling each other, US President Donald Trump and his Democratic challenger Joe Biden finally met on the debate stage.

The 74-year-old president and 77-year-old former vice president are similar in age, and they share a mutual dislike. But they differ starkly in style and substance. All of that was evident from the outset on the stage in Cleveland, Ohio.

Here are key highlights from the first of three scheduled presidential debates before the election on November 3:

– Trump came out fighting

Mr Trump is no stranger to going on the offensive, but his pugilistic approach on stage this time left his Democratic opponent fighting to complete a sentence.

Trailing in public and private polling, Mr Trump’s advisers have pushed him to reframe the election away from a referendum on his presidency to a choice between him and Mr Biden. Mr Trump, instead, commandeered the debate, trying to trip up Mr Biden by interrupting and insulting him. In the process, Mr Trump made the debate more about himself.

“There’s nothing smart about you,” Mr Trump said of Mr Biden. “47 years you’ve done nothing.”

While Mr Trump played into his reputation as a bully, it may have been effective at breaking up the worst of Mr Biden’s attacks – simply by talking over them.

Mr Trump’s aides believed before the debate that Mr Biden would be unable to withstand the withering offensive in style and substance from Mr Trump, but Mr Biden came with a few retorts of his own, calling Mr Trump a “clown” and mocking Mr Trump’s style by asking: “Will you shut up, man?”

Mr Trump’s supporters may have been cheered by his frontal assault. Whether undecided voters, who watched the debate to try to learn about the two candidates, were impressed is another matter.

Moderator Chris Wallace was none too amused, delivering a pointed reproach to Mr Trump for his interruptions. “Frankly, you’ve been doing more interrupting,” Mr Wallace said, appealing to Mr Trump to let his opponent speak.

Mr Trump is fond of superlatives, but in the case of the debate there is little doubt that it was the most acrimonious since the forums have been televised.

– Trump cannot escape coronavirus

Mr Trump has wanted the election to be about anything but the coronavirus pandemic, but he could not outrun reality on the debate stage.

“It is what it is because you are who you are,” Mr Biden told the president, echoing Mr Trump’s own words and referring to his months of downplaying Covid-19 while he said privately he understood how deadly it is.

But Mr Trump did not take it quietly. He proceeded to blitz Mr Biden with a mix of self-defence and counter-offensives.

Responding to the fact that 200,000 Americans have died from the virus, Mr Trump claimed Mr Biden’s death toll would have been “millions”. On the United States’ economic collapse, Mr Trump said Mr Biden would have been worse. He also claimed that a Biden administration would not have manufactured enough masks or ventilators.

The president went on to claim that “there will be a vaccine very soon”.

Mr Biden said: “A lot of people died, and a lot more are going to unless he (Mr Trump) gets a lot smarter.”

For voters still undecided about who would better handle the pandemic, the exchange may not have offered anything new.

– Racial tensions continue to simmer

Mr Trump said Mr Biden was the politician who helped put millions of black Americans in prison with the 1994 Violent Crime Control and Law Enforcement Act. Mr Biden called Mr Trump “the racist” in the Oval Office.

For a nation confronting a summer of racial unrest – and centuries of injustice – the debate was the latest cultural flashpoint.

Mr Biden was quiet as Mr Trump branded him as a tool of the “radical left” and a weak figure who opposes “law and order”. He pressed Mr Biden repeatedly to name any police union that has endorsed him. He falsely accused Mr Biden of wanting to “defund the police”.

Mr Biden did not capitalize when Mr Trump refused to condemn armed militias and insisted, against the guidance of his own FBI director: “This is not a right-wing problem. This is a left-wing problem.”

When asked by Mr Biden about the Proud Boys far-right extremist group, Mr Trump replied: “Proud Boys, stand back and stand by. But I’ll tell you what, somebody’s got to do something about antifa and the left.”

The former vice president tried to push back, but not until after Mr Trump had made his arguments, including the misrepresentations.

Mr Biden regained some footing mocking the president’s warnings about suburbs, saying: “He wouldn’t know a suburb unless he took a wrong turn.”

And perhaps revealing the thinking about allowing Mr Trump the rhetorical upper hand, Mr Biden said: “All these dog whistles and racism doesn’t work anymore.”

– Supreme Court question turned into a debate about healthcare

Mr Trump defended his decision to nominate Amy Coney Barrett to the Supreme Court just weeks before the election, saying “elections have consequences”.

Mr Biden said he was “not opposed to the justice” but said the “American people have a right to have a say in who the Supreme Court nominee is”.

But rather than litigate Republicans’ 2016 blocking of Merrick Garland to the high court, Mr Biden quickly pivoted to the issues that will potentially come before the court: health care and abortion. It is an effort by the Democrat to refocus the all-but-certain confirmation fight for Mr Trump’s third justice to the Supreme Court into an assault on Mr Trump and his record.

Mr Biden said Ms Barrett, who would be the sixth justice on the nine-member court to be appointed by a Republican, would endanger the Affordable Care Act, which was made law former president Barack Obama, and tens of millions of Americans with pre-existing conditions, and would imperil legalised abortion.

It was a reframing of the political debate to terms far more favourable to the Democrat, and one Mr Trump played into. Mr Trump said of the conservative Ms Barrett: “You don’t know her view on Roe vs Wade,” referring to the landmark decision of the US Supreme Court that protects a pregnant woman’s liberty to choose to have an abortion without excessive government restriction.

Mr Biden has tried to press Democrats to use the court confirmation fight as a rallying cry against Mr Trump, and the debate discussion largely played out on his turf.

– ‘Invisible’ moderator struggled to contain Trump

Debate moderator Chris Wallace of Fox News tried mightily to hold his ground after saying beforehand that it was not his job to fact-check the candidates, especially Mr Trump, in real time.

But Mr Wallace struggled to stop Mr Trump from interrupting and at times seemed to lose control of the debate.

“Mr President, as the moderator, we are going to talk about Covid in the next segment,” Mr Wallace said.

Soon after: “I’m the moderator, and I’d like you to let me ask my question.”

Minutes later: “I have to give you roughly equal time. Please let the vice president talk.”

And when Mr Wallace noted that Mr Trump has not come up with his healthcare plan in nearly four years, Mr Trump turned the question back on Mr Wallace.

He said: “First of all, I’m debating you and not him. That’s okay. I’m not surprised.”

Mr Wallace had said he wanted to be “invisible”.

That proved to be impossible.

– Trump got personal with Biden’s family

As expected, Mr Trump found a way to bring up Hunter Biden, the former vice president’s son, and recycle allegations about the younger Biden’s international business practices. Mr Biden called Mr Trump’s litany “discredited” and fired back: “I mean, his family we can talk about all night.”

But Mr Biden sidestepped any of the specifics of Mr Trump’s international business dealings and instead turned straight to the camera. “This is not about my family or his family,” Mr Biden said as Mr Trump tried to talk over him. “This is about your family.”

In a later exchange, Mr Trump interrupted Mr Biden when he was talking about his late son, Beau Biden, who died of cancer in 2015 after having served in Iraq.

“I don’t know Beau, I know Hunter,” Mr Trump said.