Everything seemed to be coming up Gary Johnson when the week started. No one liked the two major party candidates. (OK, maybe not no one but lots and lots of people.) The first presidential debate was still almost three weeks off. It looked like there might be a real chance for Johnson to make the debate stage alongside Hillary Clinton and Donald Trump!

Then Johnson went on MSNBC’s “Morning Joe.” And it all came tumbling down. Here’s the exchange between Johnson and Mike Barnicle:

BARNICLE: “What would you do, if you were elected, about Aleppo?”

JOHNSON: “About?”

BARNICLE: “Aleppo.”

JOHNSON: “And what is Aleppo?”

And, scene.

Aleppo, as you almost certainly know, is a city in Syria that has been at the heart of that country’s ongoing civil war. It has been the epicenter of the refugee crisis. It is also the oldest continuously inhabited city in the world.

Given all of that, not knowing what it is comes very, very close to disqualifying yourself when running for the highest office in the country. Which is very unfortunate if you are Gary Johnson, desperate for even the slightest crack in the electoral door to push your way through.

Johnson quickly and self-deprecatingly apologized for his mental slip and insisted it was a misunderstanding that led to him his slow-motion car wreck of an answer.

Here’s the thing: If you are a third party candidate, you might get one or, at most, two moments in the course of a campaign in which you move from the fringes of the coverage to the center of it. You must capitalize on those opportunities. It’s your only chance to make the debates. (A candidate needs to average 15 percent in a selected group of national polls to qualify.) And if you can’t make the debates, you don’t have a chance.

Johnson got that moment in the sun this past week. But it was for all the wrong reasons. His support won’t disappear entirely because, well, Trump and Clinton are still the alternatives. But any possibility of a Johnson surge just disappeared.

Gary Johnson, for swinging, missing and then injuring yourself while falling over at the one pitch you might get to hit all election, you had the Worst Week in Washington. Congrats, or something.

Chris Cillizza writes “The Fix,” a politics blog for the Washington Post. He also covers the White House.