The greatest head football coaches at the NFL and college level happen to be former colleagues and good friends.
Nick Saban was Bill Belichick's defensive coordinator on the Cleveland Browns for four seasons from 1991 to 1994, and the two have remained close while finding massive success with Alabama and the New England Patriots, respectively.
During an appearance on ESPN's "Sunday NFL Countdown," Saban shared the biggest lesson he learned from Belichick during their time in Cleveland together, and it's pretty revealing.
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Belichick gushes about McDaniels, compares Pats OC to Saban
"I think the thing I learned most from Bill was how he defined every expectation of everything in the organization," Saban said. "How you brought players to the team, how you wanted a team to look on the field, how he defined critical factors for what he expected at every position.
"That’s helped me tremendously because you know what you’re looking for all the time. A lot of coaches don’t define it so sometimes you get people that don’t fit your system."
Saban's insight helps explain why Belichick has had such consistent success with New England since 2000. The Patriots head coach is incredibly detail-oriented, and by setting those expectations throughout the organization, he makes sure every coach and player knows what to expect from themselves and others.
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Saban, who coached Mac Jones at Alabama, suggested the Patriots rookie quarterback has a similar mindset as his new head coach.
"He's a very intelligent guy, he's very instinctive," Saban added of Jones. "He does a great job of preparing for games, and he can go out and execute what coaches want him to do. That's exactly how Bill likes it."
Belichick and Saban have been the best at their craft for a long time, and their ability to get the most out of their players while picking up best practices from others have certainly helped their cause.