The two candidates weren't the only ones under scrutiny during the first presidential debate.
The performance of Lester Holt, the NBC anchor chosen to mediate, was also closely watched.
“I'm honoured to have this role, but the evening belongs to the candidates,” he said at the start of the 90-minute debate, which may explain why he then seemed to disappear.
With a clear run, Donald Trump threw out his questionable facts – saying Hillary Clinton had been fighting Isis he entire adult life, for example – with not a hint of an interruption or a follow-up from the host.
He talked over Ms Clinton, interrupting
The internet sprang into life.
Was Mr Holt missing in action? Had he got stuck in the toilet?
In advance of the debates, the Clinton campaign had pushed for the moderator to act as fact-checker.
It was easy to see why.
In the event, many of Mr Trump's bolder claims went unchallenged and Clinton supporters gnashed their teeth as the Republican nominee kept talking over their candidate.
When he did try to intervene, he resembled nothing so much as a substitute teacher trying to pacify an unruly class.
Mr Trump may have got a bit of a free ride. But his supporters weren't much happier than his, for failing to ask the Democratic candidate some tough questions.
Annoying both sides may be the sign of a win for a moderator. Or of an all round lose...
But then again, what else can you expect?
As Joe Scarborough, host of Morning Joe on MSNBC said earlier: “No matter what he does, he'll get hammered. Nobody will be happy no matter what he does.”
