ASHBURN, Va. -- Coach Ron Rivera's second season of his Carolina Panthers' tenure wasn't going so great in 2012 when his mentor, Andy Reid, reached out. Reid provided a simple reminder that not only reinforced Rivera's belief, but has stuck with him to this day.

It highlights their relationship; it also explains why Rivera isn't about to make drastic changes to his Washington Football Team despite a 2-3 start featuring an underachieving defense. When Washington plays host to Reid's Kansas City Chiefs (2-3) Sunday (1 p.m. ET, CBS), it will be the third meeting between Reid and Rivera.

Both teams are struggling, with questions about their defense. But Reid, at least, has a Super Bowl and a near decade of success in Kansas City to fall back on. Rivera is in his second year in Washington but dealing with the ghosts of two decades of fan frustration.

In Carolina, where Rivera coached from 2011 to 2019, he was in a similar spot. He took over a 2-14 team in 2011 and went 6-10 that season, but the Panthers lost six of their first seven in 2012. At one point during this stretch, Reid called Rivera -- his linebackers coach in Philadelphia from 1999 to 2003.

"When things were tough he told me, 'Keep your head up, I know you'll get through it. Stick to what you believe in, stick to your values,'" Rivera said. "That meant a lot. When he said it, it reinforced everything [that] I believe. I know we were struggling; I know it's hard and I know it feels like you're starting over. But it's one of those things where guys say, 'I get it now, I understand.' That's what happened."

The Panthers closed that year by winning six of their last seven games. For Rivera, the message applies to 2021 as well. Washington won five of its last seven games last season and won the NFC East. It hoped to build off that success, especially with a defense ranked in the top four in both yards and points allowed. That hasn't happened as Washington's defense ranks 31st in points allowed and 27th in yards.

Reid's message wasn't about not making changes, but rather not abandoning core beliefs. Reid's advice stemmed from a long career highlighted by success -- a 223-133-1 record and a Super Bowl win in 23 seasons -- and tough times. Reid lost three straight conference championships in Philadelphia and was fired in 2012 after his first losing season in seven years.

"I know various guys call him and bounce things off him," said Brad Childress, the former Minnesota Vikings coach and a Reid assistant in both Philadelphia and Kansas City. "He's always the voice of reason, the voice of calm. There are very few situations he hasn't been through. He'll have an informed opinion about why he's telling you what he's telling you."

Before his first season with Washington, Rivera picked Reid's brain.

"He's a very deep thinker. You pay attention when he says something," Rivera said.

Like others who coached under Reid, Rivera said he's borrowed multiple ideas or ways to run a team, starting with practices.

"The way he wants practice run and operated, the tempo at which he wants it played," Rivera said. "The reason is you don't condition players like you used to back in the day. So, you try to get the conditioning during the reps. It's always about tempo and practicing fast and going and doing everything quickly. It's close to ... game speed, which is really hard."

Washington cornerback Kendall Fuller played for Reid in Kansas City when it won the Super Bowl.

"Both are real competitive," Fuller said of Sunday's coaches. "Both like to get in there and talk to defensive players, offensive players. They want guys to be competitive out there. Both of them are a little strict. Both preach fundamental details. They want things done the right way, nobody walking on the field -- you run from period to period."

Reid said he liked that Rivera, working under defensive coordinator Jim Johnson in Philadelphia, was always positive with his players. But Reid also said Rivera was demanding.

"He had been there and knew what it would take to be successful," Reid said. "So, he made sure that he stayed on top of the players that way. You had a feeling he was going to be a good coordinator and you had a feeling if he got a chance to be a head coach, he'd be a good head coach."

Several years ago at the NFL combine in Indianapolis, nine of Reid's former Eagles assistants took him out to dinner to celebrate their past. Rivera had arranged for he and two others to pay the bill. But, once more, Reid took care of his guys. He had given the waiter his credit card long before the dinner had ended. Rivera didn't know the final tally, but said it was "easily several thousand."

Among the other coaches: Childress, John Harbaugh, Sean McDermott and David Culley. It turned into a Reid appreciation dinner, with Harbaugh nominated to do the talking. The other coaches said they noticed something odd in their stoic former boss: a tear in his eye, which he denied.

"Everybody nodded and said, 'Yeah I think there was a little glistening in your eye,'" Childress said.

Last year Reid's admiration for his former assistant grew as Rivera battled cancer.

"He's tougher than nails," Reid said. "You knew that as a player and I was able to see it through his coaching. Then the world got to see it, and what a great example he is for so many. For having gone through that, persevering through it, the toughness that it takes, staying positive mentally to work through it and then doing his job the way he did."