In the years following the mid-1930s, Detroit was referred to as the "City of Champions" after the Tigers, Lions, and Red Wings captured all three major professional sports championships in a seven-month period of time (the Tigers won the World Series in October 1935; the Lions won the NFL championship in December 1935; the Red Wings won the Stanley Cup in April 1936). In 1932, Eddie "The Midnight Express" Tolan from Detroit won the 100- and 200-meter races and two gold medals at the 1932 Summer Olympics. Joe Louis won the heavyweight championship of the world in 1937.

What is Detroit's sports related nickname?