FLOWERY BRANCH, Ga. -- Kyle Shanahan seemed a bit embarrassed Thursday when asked if the energy drink in his hand included electrolytes to battle a stomach virus he had Sunday during the NFC Championship Game.

“Actually, it was pretty embarrassing what happened," said the Atlanta Falcons offensive coordinator, who reportedly spent parts of Saturday and Sunday taking fluids intravenously.

More embarrassing was what Shanahan did to the Green Bay Packers.

His offense posted 392 yards passing and 493 yards total in a 44-21 victory that propelled Atlanta to Super Bowl LI against AFC champion New England.

He reaffirmed why the San Francisco 49ers appear ready to make the 37-year-old son of former NFL coach Mike Shanahan their head coach as soon as the title game is over.

Offensive coordinator Kyle Shanahan, left, and head coach Dan Quinn inherited a Falcons team that went 6-10 in 2014 and brought Atlanta to the Super Bowl. AP Photo/David Goldman

"I saw a long time ago he was going to be a good coordinator, and ultimately a good head coach," said Atlanta backup quarterback Matt Schaub, who was the quarterback in Houston when Shanahan took over the offense there.

"Just seeing how he carries himself, how he works, his knowledge of the game, man, he’s got it all. He’s ready for whatever his future holds."

Shanahan wasn’t such a hot commodity a year ago. His offense that ranks first in the NFL in scoring this season with 33.8 points a game ranked 21st in 2015 with an average of 21.2 points.

Quarterback Matt Ryan, now a leading candidate to be NFL MVP, at times looked shackled as he threw 16 interceptions to only 21 touchdowns.

Shanahan wasn’t embarrassed by those failures. He felt the Falcons were "really close" to being good. He believed that by adding speed at wide receiver, solidifying the offensive line and improving communication, the rest of the pieces were in place.

"The biggest difference numbers-wise, last year we were 32nd in the league in red zone turnovers," Shanahan said.

Ryan in particular was bad inside the 20. His red zone passer rating of 83.6 ranked 23rd in the league, far below his 108.8 this season, good for sixth. By late November 2015, he had four red zone interceptions and three fumbles.

This season, Ryan had a career-low seven interceptions and threw a career-best 38 touchdown passes during the regular season. The Falcons at times looked like the second coming of the St. Louis Rams' "Greatest Show on Turf."

This has made Shanahan look brilliant, because most people simply see he improved a team 20 spots in scoring and took it to the Super Bowl.

In reality, the jump had more to do with adding a few key players and with the players already here simply getting comfortable with a proven system than with any one thing Shanahan did.

"Everything was new to us last year," Falcons running back Tevin Coleman said. "New coaches, new staff, new everything. We had a lot of learning to do. This year, we know what we’re doing so we can play fast.

"And Kyle, he's real smart. Real smart. He just gets everybody where they need to be. He puts in a lot of great plays."

Shanahan has been around football his entire life as a son, player and now coach.

In 2008, the Texans made him the league’s youngest coordinator at 28. Houston finished third in the NFL in total offense and first in passing.

Two years later, he joined his dad in Washington as the offensive coordinator of the Redskins. By 2012, that unit ranked fifth in total offense.

After his dad was fired following the 2013 season, Shanahan went to Cleveland, where he resigned after one season because of a reported dispute with management over the mandate that rookie Johnny Manziel start.

He joined the Falcons when Dan Quinn was hired as head coach prior to the 2015 season.

The sum of all that made Shanahan realize that to succeed at any level he had to adjust. Succeeding in Washington with Robert Griffin III playing quarterback was different from succeeding in Houston where he had Schaub, Andre Johnson and Owen Daniels.

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These Falcons might be Shanahan’s most complete group in terms of talent. Having Ryan and wide receiver Julio Jones was a great starting point.

Blending in the wide-receiver speed of Mohamed Sanu and Taylor Gabriel, getting a healthy Coleman to go with Devonta Freeman at running back and adding four-time Pro Bowl selection Alex Mack at center made the Falcons arguably the league’s toughest offense to defend.

Quinn, a former defensive coordinator, is glad he doesn’t have to prepare for a Shanahan offense that can best be described as unpredictable.

"Defending the whole field, and the ability to have balance between the run game and the pass game, that’s what can make playing against our team challenging," Quinn said. "We certainly feature more players than we ever have.

"So I think that part is a real factor as well, knowing if you’re going to try to lean certain things to one player or try to take someone else out, the term we use is 'Who could set it off?'"

Schaub said the evolution of Shanahan’s offense from Year 1 to Year 2 is natural, particularly for the quarterback, who has to master a new way of doing things.

"The verbiage, the terminology, the checks and audibles we use at the line of scrimmage, a lot of it can be overwhelming sometimes from my experiences," he said.

Jones, who actually had better statistics last season (136 catches, 1,871 yards) than this one (83 catches, 1,409 yards) because more players are involved, summed up the difference in one word.

"Communication," he said.

That goes back to players having experience in the system, and to Shanahan having a better understanding of his players.

Now Shanahan gets another chance to show off his product against the league’s No. 1 scoring defense in New England. Shanahan calls it the best defense he’ll have faced all season.

He's ready for the challenge.

If he doesn’t succeed, Shanahan should be no more embarrassed about that than having the details of his stomach virus go public.