What a difference a mute button makes.
After the chaotic exchanges between United States President Donald Trump and his challenger Joe Biden at their first debate last month, Thursday night's follow-up was a more disciplined and level-headed discussion of substantive policy differences.
But without the fireworks of Mr Trump's name-calling and near-constant interruptions, the second and final face-off between the candidates was also a duller affair, with the feel of two grouchy men taking potshots at each other.
The two oldest presidential candidates in US history scored some solid zingers at the televised contest. But Mr Trump, 74, a Republican, was less energised than usual. Mr Biden, 77, spoke in broken sentences that were at times difficult to follow.
As Ian Bremmer, a prominent commentator and president of the Eurasia Group consultancy, tweeted as the candidates sparred: "Whoever you're rooting for, it's less embarrassing for the country this evening."
The rules of engagement were changed after the first debate on September 29, when Mr Trump repeatedly talked over Mr Biden and the moderator in what was widely panned as an ugly shouting match that ignored any real issues.
Trump promises Covid-19 vaccine 'within weeks' but Biden says 'dark winter' ahead
This time, the nonpartisan Commission on Presidential Debates ruled that each candidate would have two minutes of uninterrupted time at the start of each 15-minute segment, while their opponent's microphone was muted.
Afterwards, they could debate issues with each other with both microphones switched on.
Both men played by the rules and jousted about everything from environmental policy to health care, police racism and the treatment of hundreds of immigrant children on the southern border who are separated from their parents.
Mr Trump was under pressure over his handling of the coronavirus pandemic, which by Thursday morning had infected some 8,400,000 people in the United States and caused the deaths of some 222,000 — a higher share than in other developed nations.
Frequently speaking straight to the camera, Mr Biden said America was headed "into a dark winter" with a president who "has no clear plan" how to stop a virus that is multiplying in some states and is expected to worsen in the colder months.
Accusing Mr Biden of planning to shutter the US economy, the president countered: "I don't know if we're going to have a dark winter, and at all. We're opening up our country … We're fighting it and we're fighting it hard … We're rounding the corner."
Mr Trump went on the offensive against Mr Biden and his son, Hunter Biden, a recovering drug addict, saying the family should be investigated for corruption over their dealings in Russia and with the Ukrainian energy company Burisma.
President Trump claimed that Mr Biden had received $3.5 million from Moscow and that it "came through [Russian President Vladimir] Putin". Mr Biden countered by highlighting Mr Trump's foreign dealings and undisclosed US tax returns.
"Release your tax return or stop talking about corruption," said Mr Biden.
One of the testiest exchanges of the debate took place over foreign election interference, following analysis from the US intelligence community that Russia and Iran are working to influence the US election.
"Any country, no matter who it is, that interferes in American elections will pay a price," said Mr Biden while accusing the president of cosying up to Russia.
With only 12 days to go until the election, the debate was one of the last opportunities the candidates had to get their message out to millions of American viewers — including the country's elusive undecided voters.
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Mr Trump appeared to have changed his strategy for Thursday night's 90-minute debate, which was moderated by NBC's Kristen Welker and held at Belmont University in Nashville, Tennessee.
Opinion polls after the first, combative event indicated the president's hectoring had backfired and turned off voters — even though Mr Trump notched the night up as a win.
Mr Biden's average lead in national polls grew to 10 per cent from 6 per cent in the two weeks after the first debate, and to 5 per cent from 3.5 per cent across six key battleground states tracked by Real Clear Politics.
Mr Biden was able to walk on to the stage in Nashville with confidence, following the release of a Quinnipiac University poll of likely voters on Thursday that gave him a 10-point lead over Mr Trump nationally.
Still, the election is likely to hinge on Florida, Pennsylvania, Georgia, Michigan and other toss-up states where the races are tighter. Also, Mr Trump famously proved the pollsters wrong in 2016 with his surprise victory over Hillary Clinton.
