For many reasons, quarterback Jimmy Garoppolo's performance Sunday in a 48-46 comeback win over the Saints could viewed as his best since being traded to the 49ers during the 2017 season.

Garoppolo completed 26 of his 35 pass attempts for 349 yards, four touchdowns and one interception -- which came off receiver Emmanuel Sanders' hands. Simply put, he was spectacular, especially when it mattered most.

But Garoppolo's performance outside of the stats is what truly had coach Kyle Shanahan so excited. The 28-year-old QB seemed unfazed in the Superdome, perhaps the most raucous stadium in the NFL.

"The thing that impressed me the most was just how he handled the noise," Shanahan said to reporters in Santa Clara on Monday. "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."

In fact, Saints fans -- and well-traveled 49ers fans -- were so loud in New Orleans that Shanahan had to call a timeout in the most critical moment of the game. With only 39 seconds remaining, and San Francisco trailing 46-45, the offense had to regroup as Garoppolo heard "15" instead of "14."

"Four and five, you know, and you just couldn't hear it," Shanahan explained. "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 throughout the whole time."

Luckily for the 49ers, they still had two timeouts left and were able to go over the game plan. The two numbers were much different plays. Shanahan noticed how the offense lined up and quickly made the adjustment.

With the game on the line, Jimmy G hit tight end George Kittle -- who went full beast mode -- for a 39-yard gain, plus 14 more yards from a facemask penalty.

George Freakin’ Kittle 😱😱😱pic.twitter.com/y7ywfKYM2L — 49ers on NBCS (@NBCS49ers) December 8, 2019

[RELATED: What Jimmy G told Kittle before 49ers' biggest play of year]

Garoppolo had full control of the offense in an epic back-and-forth battle in the Bayou. Quarterback and coach were on the same page, remaining calm when they easily could have become rattled.

The next test comes this Sunday against the Falcons as the 49ers look to keep control of the top seed in the NFC, but this time, they'll be in front of their home fans at Levi's Stadium.