[2] Along with other members of his family, Mayes was registered in 1906 at the age of one year on the Dawes Rolls as "Cherokee by Blood" (1/8).

[2][7][8] McLain attended the Haskell Institute in Lawrence, Kansas,[9] a college founded for Native Americans of various tribes.

The Lawrence Journal-World reported, "The Husky Cherokee fullback thrilled the fans by his broken field running and his vicious tackling.

"[11] In the fourth game of the 1926 season, McLain scored four rushing touchdowns in a 38-0 victory over Morningside College.

[10] For their fifth game, Haskell traveled to Ohio to play the undefeated Dayton Triangles professional football team.

[10] In the seventh game of the season, McLain rushed for 129 yards and two touchdowns on 27 carries in a 36-0 victory over Bucknell.

[10] McLain returned to the lineup in a 27-0 victory over an undefeated Xavier College team on Thanksgiving Day in Cincinnati.

At the start of the 1928 season, the United Press ran a feature story describing Mayes as the "Big Hope of Hawkeye Gridders.

McLain, a 210 pound, fair haired young giant who stands six feet two inches in his stocking feet and crashed the line in a manner which brings back memories of Gordon Locke, Iowa's All-American fullback of championship days, is the big hope of the Hawkeyes.

"[17] When the Iowa team played at Chicago's Soldier Field in October 1928, The New York Times wrote:"Not since the days of Red Grange has Chicago and the Big Ten been as intensely interested in a single gridiron luminary as they are in that giant Indian line smasher, Mayes McLain of Iowa.

Weighing more than 215 pounds and standing six feet two inches, McLain, who led in individual scoring while at Haskell two years ago by burning up 253 points in thirteen games, is a terrific driver.

[19] The New York Times reported: "Mayes McLain, giant Indian fullback, swept the lighter Chicago team off its feet.

[22] In January 1929, McLain announced that he was working with Iowa's baseball coach "in an attempt to master the art of pitching.

"[23] That spring, allegations circulated that Iowa was paying athletes in violation of conference rules.

An investigation revealed that a group of alumni had created a "Labor Fund" for the purpose of promoting work for Iowa athletes in local businesses.

McLain had been paid $60 per month during the 1928-29 academic year "for allegedly taking a 'real estate census' of Iowa City.

He was matched up against many of the most famous wrestlers of the day, including Strangler Lewis, Ed Don George, Ray Steele, and Wee Willie Davis.