In 1981, Jim Caldwell was a 26-year-old assistant coach on a Northwestern team in the midst of a Big Ten record losing streak. Eager to gather knowledge that would help his team and boost his career, he began looking for a pro team that would let him observe a practice.

When he reached out to the Oakland Raiders, owner Al Davis said he’d let Caldwell do a lot more than just watch a practice.

“Some pro teams wouldn’t let you in. One team that I had heard would let me in was the Oakland Raiders,” Caldwell said this week. “Coach Davis let me come in, and he spent three days with me. He walked around with me personally. He took time with me, walked me around at practice. He never left my side at practice. We’d walk over there with drill work, go through it, and at night time he’d come back in at night and he and I would watch film from 10 o’clock at night until the wee hours of the morning. Three days in a row, and this was a guy who was running the whole operation.”

Caldwell has never forgotten the kindness Davis showed him. So now that Caldwell is the Lions’ head coach, the team has an open-door policy to high school and college coaches. At Organized Team Activities this week, several coaches came to watch and learn from the Lions.

“Obviously there are no pro coaches here, but colleges, high schools — I think it’s incumbent upon us to give these guys an opportunity to come in and kind of see how we do it, what we do,” Caldwell said “So, from that experience I really believe in allowing guys to come in and see what we do. I think that’s the way it should be. It helped me out tremendously in my career.”

Davis died in 2011, but he’s left a lasting legacy in the NFL. That legacy now extends to young coaches who are benefitting from Caldwell’s adoption of Davis’s open-door policy.