The wise words worked immediately. The 33-year-old is now the youngest coach ever to lead a team to a Super Bowl.
McVay turned to his grandpa years ago and asked former 49ers general manager John McVay what it took to obtain a sustained level of success.
"He said 'because our best players were the example of what it looked right to do right and everybody else fell in alignment because that was the standard and nobody was above that,'" the elder McVay said.
Several Rams players say McVay's best attribute is transparency. From rookies to veterans, players respect the coach's honest approach and approachability. He has used that transparency to form a bond with his team and pass on his knowledge to the Rams' leaders.
Rams defensive tackle Ndamukong Suh first spoke to McVay through the team's director of training and performance, Ted Wrath, before suiting up for the franchise after signing this offseason.
"I will always compare every head coach to Jim Caldwell, who I have the utmost respect for in running an organization from the head coaching position," Suh said. "There are a lot of similarities between Jim Caldwell and Sean McVay. I got a lot of respect for Sean. He's very transparent and I super respect that."
He added: "That's not common in the NFL."
Something else uncommon in the NFL has been the Rams' rapid rise from a tepid team in the cellar of the NFC West to a perennial power with a feared offense, now on the cusp of hoisting a Lombardi Trophy. Jeff Fisher's Rams posted a 31-45-1 record and never finished better than third place in the division during his five-year tenure.
McVay pushed the squad to a seven win improvement in his first season, led by the No. 1 offense in the NFL. This season, the Rams somehow exceeded expectations, winning 13 games and scoring a franchise-record 527 points.
Rams cornerback Aqib Talib said the first thing that he noticed about McVay was his command of a room. Talib, who is just a few weeks younger than his coach, joined the Rams this offseason. He played for Bill Belichick in two postseasons before snatching a Lombardi Trophy in 2016 with the Denver Broncos.
"I remember when I first got out here, that first team meeting, I just remember how he had everybody's attention," Talib said. "How everyone was buying into what he was saying. That was April. The head coach had guys behind what he was saying in April. That's a great sign."
Talib and Suh weren't around to see the Rams' transition from bad to behemoth. But Aaron Donald was. Fisher selected the Pittsburgh product with the No. 13 overall pick in the 2014 NFL Draft. While Donald made the Pro Bowl in his first season and was an All-Pro in his second and third seasons, he really exploded under McVay.
He has morphed from a great defensive tackle to the premier player at the position. Donald is now the best defensive player in the NFL and has the hardware to prove it. He is what John McVay would call an "example of what it looks like to do right."
Donald is expected to win his second consecutive Defensive Player of the Year award Saturday in Atlanta, on the eve of facing the New England Patriots in Super Bowl LIII.
He said the difference with McVay and past coaches is that McVay "held people accountable." Donald said that accountability -- and bringing in other great coaching minds -- is what led the team to the Super Bowl.
"The first time you sit down and talk to him, you hear how he is talking," Donald said. "He wants to be great.
"He has a mindset to be great. He is nonstop working, nonstop trying to find ways to get better and get this team better. When you have a coach like that, with that type of mindset, it doesn't do nothing but feed you and make you want the same things. You just have to follow that guy's lead. He's definitely a special coach."
Rams quarterback Jared Goff said McVay has taught him a lot about character and being a leader. The former No. 1 overall pick has been another example of a best player setting a standard. His stoic demeanor and Pro Bowl production has seeped into the Rams on the offensive side of the ball.
John to Sean
John McVay, 88, began coaching at the college level in the '50s. He went on to serve as an assistant at Michigan State before head coaching tenures at Dayton and Memphis Southern. He became the New York Giants' coach in 1976 and posted a 14-23 record in that role. He became the 49ers' general manager in 1983.
McVay's 49ers were 108-34-1 during his nine-year tenure as general manager. The 49ers won three Super Bowls and went to the postseason every year, led by legends like Jerry Rice, Steve Young, Joe Montana, Ronnie Lott and Charles Haley, among others. Rice and Young were first-round picks, while Haley proved to be a fourth-round steal in the 1986 Draft for McVay.
Haley is tied with Brady for the most Super Bowls won by a single player (five). McVay's grandson could keep Brady from passing the Hall of Famer for the most all-time with a win Sunday.
John McVay and his wife had three sons, including Sean's father, Tim McVay. He would take his young son to practices where he had the chance to watch and meet Rice, Montana, Young and legendary coaches.
John McVay also hired Jon Gruden's dad as an assistant coach at Dayton, a move which eventually led to his grandson joining the NFL ranks under Gruden.
Now McVay is forming his own coaching tree, with his assistants being eyed for head coaching gigs.
Five players older than McVay will take the field on Super Bowl Sunday. The Rams roster two of them in left tackle Andrew Whitworth and center John Sullivan. The Patriots' Tom Brady, Stephen Gostkowski and Matthew Slater are also McVay's elders.
Belichick is exactly twice McVay's age. But it hasn't stopped the 66-year-old from relating to the rising star. The Patriots' coach sent advice via text message to McVay throughout the season, and the two have developed a friendship.
Belichick called the Rams "very well-coached" when asked about McVay on Monday at Super Bowl Opening Night.
"I was just so appreciative of somebody of his nature to even take the time to send a text after we had won a game earlier this year," McVay said. "To get a chance to have the platform and be able to get the chance to meet people like coach Belichick that are willing to share and help, that means a lot.
"When you look at these guys and what they've done in terms of consistency, that's really the truest measurement of performance and nobody has done it better than they have over the last handful of years. That's why you have so much respect and appreciation for them."
While Talib maintains that Belichick's Patriots are "the best" until further notice, McVay could be on his way to changing that narrative.
"I've got a lot of respect for coach Belichick. I feel like they are the best," Talib said. "If you win, you want to play against the best. So there is no discrepancies or nothing. It's going to be an honor to play against those guys."