2. Potsy Clark
Tied for second, with George Willson, all-time in career coaching wins on Detroit's leaderboard is Potsy Clark, who went 53-25-7 with the Lions. Clark would coach Detroit from 1931 to 1940, and was able to win one NFL Championship during that time.
His two best seasons came in 1934 and 1935. In '34, Clark's Lions went 10-3 and then won seven games the following year.
To this day, Clark's winning percentage (.679) is the highest among all Lions head coaches in team history. He did, also, coach in an era where there were far less teams and the competition was not as heavy. But, still, the percentage is impressive and holds up.
Before coaching in Detroit, Clark would spend time with what is now known as Michigan State University, the University of Kansas, Butler University and the University of Nebraska-Lincoln as a coach. Following his days in Detroit, Clark would go on to become the athletic director back at Nebraska.