[1] A native of Ranger, Texas, in his playing days, he stood 5 ft 11+1⁄2 in (1.82 m) (181.6 cm) tall, weighed 195 pounds (88.5 kg), and threw and batted righthanded.

[2]) He lettered in football, basketball, track and baseball at the University of Oklahoma and was named all-Big Six quarterback.

He played the rest of his MLB career in the American League, for the Boston Red Sox, St. Louis Browns, New York Yankees and Cleveland Indians (1937–40; 1942; 1946).

[2] He was the interim manager of the 1953 Redlegs, finishing the unexpired term of Rogers Hornsby, who resigned late in the season.

[2] After his coaching career, Mills spent many seasons as a scout for the Kansas City Athletics, then the Yankees.