The Mercedes-Benz Superdome, even with a strong contingent of the Niner Faithful in the stadium, was a troublesome environment for the San Francisco 49ers. That was evident during the 4th-and-2 play that eventually saw quarterback Jimmy Garoppolo hit George Kittle, followed by the tight end fighting and pulling defenders (one from his face mask) for a 39-yard gain. It was capped off by a 15-yard penalty.

The drive concluded with Robbie Gould kicking a game-winning field goal as time expired to lift the 49ers to a 48-46 victory and an 11-2 record.

That fourth-down play almost looked very different, though, and may not have had such a positive result if not for a quick timeout called by head coach Kyle Shanahan before the ball was snapped. The play call that Garoppolo heard and the one that Shanahan sent into the huddle didn't match, and that was because of the crowd noise.

"The thing that impressed me the most was how [Garoppolo] handled the noise," Shanahan told reporters on Monday as he started to explain what happened on that play. "I've been in that stadium a lot, but it was louder than usual to me. You never can hear at the line, but it was very hard for him to hear in the huddle. That's why we had to call a timeout on that 4th-and-2.

"I called a play that had '14' in it, but it sounded a heck of a lot like '15.' ... You just couldn't hear it. So that stuff was happening a lot, and for him to just still keep his poise, and try to fix things a lot in the game, he kept our guys pretty cool the whole time."

Shanahan confirmed that the difference between '14' and '15' in the play call could have led to an offensive disaster.

"Wrist band No. 15 is a lot different than wrist band No. 14," Shanahan explained. "And you don't really know until they line up there, and it's a pretty big time in the game, and you're also trying to save your timeouts, too. ... I didn't know exactly what [Garoppolo] missed because I didn't know what '15' looked like at the time, but I knew it didn't look like '14' when they lined up.

"Fortunately, we had a timeout, and we [used] it. And then, fortunately, the next play was a good play."

The 49ers may not have to worry about the Superdome noise again this year. With the win, San Francisco will most likely host any 49ers-Saints playoff rematch, should the two teams meet again, at Levi's Stadium.