OWINGS MILLS, Md. -- It has been over a decade since John Harbaugh was on Andy Reid's staff, but the Baltimore Ravens coach will forever carry two words from his time with him.
Harbaugh, a longtime special-teams coach with the Eagles, remembers walking into Reid's office in their first year together and always seeing a 3-by-5-inch card right behind his desk. It had two words written on it: "Don't Judge."
In their nine years in Philadelphia (1999 to 2007), Harbaugh never asked Reid about the message behind it. For Harbaugh, the meaning was clear.
"You don’t bring all your stuff into the thing," Harbaugh said. "Take people for who they are and for where they’re at in their life -- as football players, as coaches, whatever –- and let them be who they are. Help them along the way where you can. Give them good advice."
Sunday's high-profile battle between the Ravens and Kansas City Chiefs is full of intriguing matchups. It pits the NFL's No. 1 defense against the league's highest-scoring offense. It showcases two of the most talked-about young quarterbacks in Lamar Jackson and Patrick Mahomes.
It also features the eighth-winningest coach in NFL history (Reid) against his most successful pupil (Harbaugh). While winning a Super Bowl and guiding Baltimore to the playoffs in six seasons, Harbaugh still thinks of everything he has picked up from Reid, whether it's attention to detail, fatherhood or meals the night before games.
Harbaugh credits much of his success to Reid taking a chance on him. When Reid took over as Eagles coach in 1999, he kept only three assistants from Ray Rhodes' staff: offensive line coach Juan Castillo, running backs coach Ted Williams and Harbaugh.
Reid knew Harbaugh's father, Jack, who has the head coach at Western Kentucky at the time and was good friends with Rhodes, who endorsed Harbaugh.
"So, with all those things, I found out for myself that he’s a phenomenal coach," Reid said. "I have a ton of respect for him."
This marks only the fourth time that Harbaugh has faced Reid, who has a 2-1 record against his former assistant. Among Reid's impressive coaching tree -- which includes Doug Pederson, Ron Rivera and Sean McDermott -- Harbaugh can become the first to beat Reid twice.
"One of the most important things in any profession is where you start," Harbaugh said. "Who you start with really makes a big difference. If you start with people that do it the right way -- good people, teach you the right things -- it just gives you a chance, gives you a leg up. And Andy, for me, was a big part of that in every way."
Here are some of Harbaugh's memories of Reid throughout the years:
On attention to detail: "I know this, don't make a mistake because Andy's teams aren't going to. He's taught us well. We're just trying to do it better than he does it. That's the big challenge."
On fatherhood: "Alison [Harbaugh's daughter] was raised in Philly. Andy was one of the first ones to talk to me about being a good parent, besides my dad and mom. I remember the first thing Alison did when Andy held her was she grabbed his mustache and just pulled it as hard as she could."
On the meal night before game day: "We tried to replicate that in Baltimore. It starts with cheeseburgers. We don't do the Haagen-Dazs [ice cream]. I took a lot of heat because we had Haagen-Dazs the first couple of years. We cut the Haagen-Dazs out at the behest of our nutrition expert."
Harbaugh and Reid are among the top five winningest active coaches in the NFL, with only 8 percentage points separating them. Reid is 204-135-1 (.602), and Harbaugh is 111-76 (.594). Sunday's game will be the first time they'll meet in three years, and it carries major playoff implications in the AFC.
As for that index card that Harbaugh remembers so fondly, Reid still has it in his office.
"Are you going to sit there and judge, or are you going to teach?" Reid said in explaining the message to Baltimore reporters. "I want to teach, and so that’s what I feel like I’m here for, is to do that. And then, whatever player is given to me, I’m going to try to do that to the best of my ability and not get caught up in all the nonsense of judging."