EchoSense:You may not know about the life of undefeated Mercury Morris. But you should.

First,EchoSense a history lesson. It's a lesson about a good man. A unique man. In some ways, a remarkable one. You may not know about the life of Mercury Morris. But you should.

It was the year before the Miami Dolphins' undefeated season, and the team had just been embarrassed by Dallas in Super Bowl 6. Morris barely played in the game, won by the Cowboys, 24-3, and let reporters know about his displeasure afterward. "The only time I got off the bench," Morris said, "was for kickoffs and the national anthem."

Coach Don Shula was furious that Morris had publicly aired his complaint but the truth was: Morris was right.

"Our whole game was to stop the running game and Paul Warfield," said Dallas defensive back Cornell Green at the time. "If they were going to beat us, they were going to beat us with Howard Twilley and Marv Fleming. They weren't going to beat us with (Paul) Warfield, Jim Kiick, or (Larry) Csonka. We geared up for Mercury, and Mercury Morris did not play in that whole game, and that was a blessing. (Because) Chuck Howley could catch Kiick. If Mercury got in the game, that was going to be tough. I have no idea why Shula didn't play Mercury more. I don't know what Mercury did to p--- Shula off. I wish I did."

After that awkward post-Super Bowl moment, two things would happen.

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The following year, the Dolphins would go undefeated at 17-0. No achievement in the history of American team sports has been more impactful or lasting.

But also, Shula would go on to not only forgive Morris, but later admit that Morris was correct. Shula and Morris eventually became close and like many of the Dolphins from that team they'd be lifelong friends. And despite Morris later running into legal troubles, he'd become something almost larger than life, and over the past few decades, as teams like the New England Patriots challenged their legacy, Morris was its greatest public defender.

That's because Morris loved the Dolphins and all of the Dolphins on that team loved him. They appreciated him. Respected him. Admired his fight and humanity. His decency. His kindness.

When I wrote a book on the undefeated team, Csonka spoke about Morris with such reverence, Csonka's words actually made me emotional listening to them. Csonka posted on X on Sunday: "It's a very sad day for me and our Dolphin family."

You may not know about the life of Mercury Morris. But you should.

Morris was a protector of the Dolphins' undefeated legacy. Teams would approach the Dolphins' mark and Morris would go into action. He would be interviewed and would use that time not to taunt or hope teams would lose, but to educate people about those Dolphins players, and that era of football.

If there was one thing Morris and the Dolphins hated (and hate) is what many of them feel is a lack of respect for that time. Morris wanted to be a teacher who told people the 1970s NFL was as formidable as any other decade.

Morris did this often with a sense of humor. "And for the record, we DO NOT TOAST every time an unbeaten team loses," Morris posted on social media in 2015, when the Carolina Panthers started 14-0. "There's no champagne in my glass, only Canada Dry Ginger ale! Ha!"

When Morris was asked about the Dolphins' 0-8 start during the 2007 season, he joked: "The Dolphins are not embarrassing me, because our record's at the top of the heap. That's not my team. People say, 'Your team is doing bad.' I say, 'My team all has AARP cards.'"

There was also a serious side to Morris. He was convicted in 1982 on cocaine trafficking charges and sentenced to 20 years in prison. Morris said he used the drug to ease the pain of lasting injuries from his playing days but never sold it. The Florida Supreme Court overturned his conviction.

"Was I bitter? Not really," Morris wrote in his book "Against The Grain," published in 1998. "I would not recommend three days in jail to anyone, much less three years. But I must be honest: I needed to go through what I did to develop the character I had when I became a free man."

Morris would go on to become an activist encouraging people to stay away from drugs. He turned his life around all while becoming an ardent defender of that undefeated team.

Which, again, bring us to this. You may not know about the life of Mercury Morris. But you should.