 .I never expected it to last 45 years.” Asked at the time of his retirement from coaching in 1970 if he would finally open his law practice, Keen joked, “I'm going into the full practice of retiring, I think.” He took three years off from coaching to serve as a Naval Commander during World War II.“When I came out of the service I definitely, positively decided I had to start my law practice, but Fritz Crisler persuaded me to keep coaching.” The military leave of absence from 1942 to 1945 still counted as years of service at the University of Michigan.