Just when you think you've seen everything in the NFL, you see something new. It happened Sunday as the Saints lost at home to the Broncos in just about the most unimaginable way: A Drew Brees touchdown tied things up at 23, but the Broncos blocked an extra point and took it to the house for two points to win.

It wasn't quite a walk-off, because the Saints still had to attempt an onside kick (after having a team score go-ahead points on them no less).

Let's start from the beginning and run through everything that happened.

1. Brees throws a dart

The Saints were trailing by three with more than two minutes left on the drive before this one and Michael Thomas coughed the ball up for the second time. New Orleans' defense stood tall and got Brees the ball back. He marched down the field and threw a bullet to Brandin Cooks for the score.

Pretty incredible moment. Season-saving stuff from Brees and the Saints offense.

Just when the Saints thought they were toast, Brees brings them right back. They are an extra point away from beating Denver at home at this point and really putting themselves in a good position in the NFC South (the Panthers and Falcons have both essentially lost at this point).

2. Now the extra point

Kicking is no longer automatic in today's NFL and it was never more evident than when Wil Lutz stepped up to kick the extra point. It was summarily blocked by the Broncos but not just blocked to save the game from being over, it was blocked and then returned to basically end the game.

3. The kick itself

Worth noting: the blocked extra point was extremely well-played by the Broncos, who appeared to be coached up to push down players on the Saints line and open up a hole for blocking.

4. The return

But this is where things get REAL annoying if you were hoping the Saints would win this game. Not only are the Broncos sprinting back with a game-winning reverse two-point conversion, but it sure looked like Broncos safety Will Parks stepped out of bounds.

via NFL Broadcast

Let's zoom and enhance:

via NFL Broadcast

That isn't entirely definitive without a view from the sky, but this is 2016 so we should have that. And we do.

via NFL Broadcast

The view from the sideline also pretty clearly shows that Parks steps out of bounds.

via NFL Broadcast

You look at these three angles and it's pretty clear that Parks stepped out of bounds. Every single person on the Saints sideline was pointing and screaming at Parks after this moment on the return -- watching it on replay it was hard to imagine the refs not overturning the play and resetting the score at 23-23.

Somehow the refs couldn't overturn the ruling.

5. The problems

Surprisingly, Sean Payton wasn't fired up about the final play. You'd think he would've been lit up over not having the play overturned.

As I noted on Twitter, the biggest issue for the refs was Parks wearing white shoes. Because his shoes didn't contrast with the sideline, it was impossible to tell whether or not he definitively stepped out of bounds.

Payton agreed.

And the other issue is there's not absolutely lock-down look at the play because the NFL doesn't have sideline or end zone cameras installed. If that was the case we'd be able to zoom and enhance at the NFL office and determine with absolute certainty whether or not Parks was out of bounds.

That's not the case and the Saints suffered a bizarre, heart-breaking, two-point loss as a result.