LOS ANGELES -- Jon Embree left his job coaching Washington Redskins tight ends to become head coach at Colorado in the second week of December in 2010. Four games remained in the Redskins' season. Chris Cooley, by that point one of the game's most productive tight ends, quickly became uneasy about what would follow. His new position coach would be Embree's assistant, a 24-year-old named Sean McVay, and Cooley was skeptical.

It took one day to reverse that.

"This 24-year-old kid came in and knew everything about the offense, and everything about everything," Cooley said. "I learned more about football than I had in my entire career in four weeks."

New Rams coach Sean McVay draws comparisons to Jon Gruden because of his unbridled enthusiasm for the game. John McDonnell/The Washington Post via Getty Images

In McVay, Cooley saw peerless intelligence and remarkable self-assurance. McVay didn't just know the offense by heart or direct his tight ends in great detail; he was able to explain why. Cooley began to see the game from a wider scope and quickly developed an admiration for McVay, even though the coach was four years younger and had never played an NFL snap. In the 2011 opener, Cooley broke the franchise record for receptions by a tight end and gifted McVay the football. Today, Cooley credits McVay for the way he sees the game.

"His ability to understand the game from every aspect -- fronts, coverages, line play, checks, from top to bottom -- is uncanny," Cooley, now a member of the Redskins' radio broadcast team, said in a phone conversation Saturday, the day after McVay was introduced as the Los Angeles Rams' head coach. "To understand it in that way and to speak it the way he speaks it, it’s just a love thing. You have to spend unlimited time doing it. And it has to be what you love. When you talk to him, when I talk to him, you just hear it in his voice. You see it."

Growing up with the 49ers

The love began with his upbringing. McVay's grandfather, John, was an executive for the San Francisco teams that won five Super Bowl titles in the 1980s and '90s. McVay's father, Tim -- an accomplished safety for Lee Corso-led Indiana teams -- immersed McVay into that environment as often as he could. As a toddler, McVay would watch 49ers practices and sometimes find himself within earshot of conversations between his grandfather and Hall of Fame coach Bill Walsh. He idolized Joe Montana and Steve Young, then later got to know Jeff Garcia.

Tim will tell you Sean learned "a ton" from his grandfather, even though he was so young when John's front-office career was winding down.

"He learned how to interact with people," Tim said. "He learned how to treat people."

Sean was born in Dayton, Ohio, and raised in Atlanta, where his dad now runs the local ABC affiliate. He began to learn how offenses worked as a read-option quarterback in high school. By that point, Tim began seeing Sean engage in high-level conversations with his coaches. He watched his son serve as a receiver and return specialist in Miami (Ohio), then begin his coaching career as a low-level assistant, and then, eight years later, become the youngest head coach in the NFL's modern era at age 30.

Yes, Tim is surprised it all happened so quickly, but:

"He’s absolutely capable of this," Tim stressed. "It’s not too big for him. I can tell you."

Getting started in the NFL

Sean got his first NFL job in 2008 under then-Buccaneers coach Jon Gruden. In 2009, McVay became an assistant on a team called the Florida Tuskers in the now-defunct United Football League, which had Jim Haslett as the head coach and Gruden's younger brother, Jay, installed as the offensive coordinator. When he became the Redskins assistant tight ends coach in Washington, Mike Shanahan ran the team and his son, Kyle, ran the offense.

It was about that time when Sean began reading books on leadership, gravitating towards those centered on Walsh and legendary UCLA basketball coach John Wooden. His favorite is called "The Score Takes Care of Itself: My Philosophy of Leadership." Walsh wrote it, and John McVay has his own chapter. The central question he searches for in his reading, McVay said, is: "How can you figure out ways to develop and build relationships that are authentic and genuine?"

Bears tight end Logan Paulsen, who spent 2010-15 in Washington, was amazed at how McVay remembered the names and backgrounds of every Redskins employee, from coaches to cooks to janitors. Standout Redskins tight end Jordan Reed wanted to keep working specifically with McVay even after he became the offensive coordinator in 2014. The following season, McVay began to call plays and Cooley marveled at the way he inflated the confidence of quarterback Kirk Cousins, a fourth-round pick who spent his first three seasons stuck behind Robert Griffin III.

"He has a way, this ease about him," Paulsen said. "He talks football all the time, but he finds a way to speak to you."

Making his mark

Sean McVay's scheme and ability to communicate helped Redskins QB Kirk Cousins flourish. AP Photo/Alex Brandon

Under McVay's watch in 2015, the Redskins scored the NFL's 10th-most points and won the NFC East behind Cousins, the first-year starting quarterback who posted a 126.1 passer rating in the second half. Heading into the 2016 season, Cooley told everybody willing to listen that McVay would be an NFL head coach the following year. They all basically told Cooley he was crazy, but then the Redskins gained more yards than all but two teams and McVay began to be taken seriously as a head coaching candidate.

McVay blew teams away during the interview process, then signed a five-year contract with the Rams and said he's "embracing the expectations, the situation, and the city of L.A."

He inherits an offense that has been the NFL's worst each of the past two seasons and will take on the playcalling duties. McVay's greatest gift as a playcaller is his knack for consistently putting players in positions to succeed, which might best be characterized by his success on third down. The Redskins ranked third in the NFL in third-down percentage these past two seasons, while the Rams were dead last.

In that time, McVay did a masterful job of putting the Redskins in the favorable third-down situations that allowed them to convert at a high rate. The Redskins needed three or fewer yards on 32.2 percent of their third-down plays this season, fourth-best in the NFL, according to ESPN Stats & Information.

The next Jon Gruden

Cooley likes to joke that when McVay's alarm goes off before sunrise, he shoots his fist in the air with great enthusiasm.

"I don’t sleep much," McVay admitted. "If you can tell, I’m a little wired, a little high strung."

The Saturday before the Redskins' regular-season finale against the Giants, Cooley walked into the facility at 5 a.m. thinking he would be alone. McVay was already in the film room. "Look at this!" he said, showing clips of plays run against the Browns and Falcons that had nothing to do with the upcoming game plan. Cooley said he's "never met anyone who liked the game of football more than Sean McVay, and it’s not even close."

His unbridled enthusiasm bears a striking resemblance.

McVay's agent, Bob LaMonte, a pioneer when it comes to representing prospective coaches, first met McVay about four years ago and came away thinking: "This guy is the next Jon Gruden.

"The dynamic, the brain, everything about him," said LaMonte, who has also represented Gruden for decades. "I had lunch with him and said, 'This guy is electric.' Jon Gruden was electric."

It isn't just that Jon Gruden gave McVay his first job. It's that McVay took part in Gruden's Fired Football Coaches Association in 2009 and learned so much about what it took to be a head coach. It's that Gruden's father, Jim Gruden Sr., was close friends with McVay's grandfather and then recruited McVay's father in college. It's that Gruden, in McVay's words, "truly taught me to look at the game from a 22-man perspective."

Gruden helped advise the Rams as they went about searching for their new coach and raved about McVay. The Rams interviewed McVay for the first time on Jan. 5. And right in the middle of it, COO Kevin Demoff, who led the search, shot Gruden a text that read: "Holy crap, he is you."

The voice, the cadence, the gestures, the intensity.

"One of the things that stands out about Jon is when you’re in a room with Jon, you always feel Jon," McVay said. "He’s got a presence about himself. That’s something that I think is important. I’d like to be described that way."

ESPN's John Keim contributed to this report.